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  • Javascript CSS visability.

    - by Alex
    It seems that javascript only can ready inline css if i want to check if element is display:hidden getting it with: el.style.display But how to check if display:none is placed inside external CSS file?

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  • .htaccess not load css file and images and duplicate parent url?

    - by Mahran Elneel
    i have create htaccess and cannot load css file and images but when add ../file.css and images ../ima it work but i want to open in current directory. and when click the link in home page like will be http://localhost/mysite/program/4 but in another page will add http://localhost/mysite/program/program/2 and this wrong location the .htaccess code Options +FollowSymLinks RewriteEngine On # Turn on the rewriting engine RewriteRule ^program/([0-9]+)/?$ get_programs.php?pack_id=$1 [NC,L] RewriteRule ^El-Mensajero/?$ home.php [NC,L] RewriteRule ^Daily-Tours/?$ daily_tours.php [NC,L] RewriteRule ^page/([0-9]+)/?$ get_pages.php?page_id=$1 [NC,L]

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  • get attributes from xml tree using linq

    - by nelsonwebs
    I'm working with an xml file that looks like this: <?xml version="1.0" encoding="UTF-8"?> <element1 xmlns="http://namespace1/"> <element2> <element3> <element4 attr1="2009-11-09"> <element5 attr2="NAME1"> <element6 attr3="1"> <element7 attr4="1" attr5="5.5" attr6="3.4"/> </element6> </element5> <element5 attr2="NAME2"> <element6 attr3="1"> <element7 attr4="3" attr5="4" attr6="4.5"/> </element6> </element5> </element4> </element3> </element2> </element1> Where I need to loop through element5 and retrieve the attributes in an Ienumberable like this: attr1, attr2, attr3, attr4, attr5, attr6 using linq to xml and c#. I can loop through the element5 and get all the attribute2 info using but I can't figure out how to get the parent or child attributes I need. UPDATE: Thanks for the feeback thus far. For clarity, I need to do a loop through attribute5. So basically, what I have right now (which isn't much) is . . . XElement xel = XElement.Load(xml); IEnumberable<XElement> cList = from el in xel.Elements(env + "element2").Element (n2 + "element3").Elements(n2 + "element4").Elements(ns + "element5") select el; foreach (XElement e in cList) Console.WriteLine(e.Attribute("attr2").Value.ToString()); This will give me the value all the attr 2 in the loop but I could be going about this all wrong for what I'm trying to acheive. I also need to collect the other attributes mentioned above in a collection (the Console reference is just me playing with this right now but the end result I need is a collection). So the end results would be a collection like attr1, attr2, attr3, attr4, attr5, attr6 2009-11-09, name1, 1, 1, 5.5, 3.4 2009-11-09, name2, 1, 3, 4, 4.5 Make Sense?

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  • JSF action, value and binding catalog generator

    - by BBSnowman
    I am looking for a simple tool that generates a catalog of all used action methods, values and bindings. I'm working on a big JSF/RichFaces project and I have lost the overview of the used links to the beans. Therefore I need a tool (would be nice if it is a Eclipse plugin) that generates a simple list of all used EL expressions. Is there something out there?

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  • jQuery Validator - Dynamic Text

    - by James
    Adding a validator to my form: jQuery.validator.addMethod('whatever', function(val, el) { // whatever goes here }, 'A maximum of ' + $('#my_id_here').val() + ' categories can be selected.'); This doesn't fly. I always get undefined. Is this a good, simple way to do this? Thanks

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  • home directory and .emacs file in Windows 7

    - by prosseek
    I installed emacs 23.3.1 in c:/emacs-23.3. Following the hints in this page, I updated the site-start.el to set HOME environment variable. (setenv "HOME" "c:/users/USER/emacs") And I made c:/users/USER/.emacs (like I did in unix/mac) to write the code for using slime, but it doesn't seem to start slime correctly. Is this a correct way of setting emacs in Windows 7? Where do I put the .emacs file?

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  • json data not rendered in backbone view

    - by user2535706
    I have been trying to render the json data to the view by calling the rest api and the code is as follows: var Profile = Backbone.Model.extend({ dataType:'jsonp', defaults: { intuitId: null, email: null, type: null }, }); var ProfileList = Backbone.Collection.extend({ model: Profile, url: '/v1/entities/6414256167329108895' }); var ProfileView = Backbone.View.extend({ el: "#profiles", template: _.template($('#profileTemplate').html()), render: function() { _.each(this.model.models, function(profile) { var profileTemplate = this.template(this.model.toJSON()); $(this.el).append(tprofileTemplate); }, this); return this; } }); var profiles = new ProfileList(); var profilesView = new ProfileView({model: profiles}); profiles.fetch(); profilesView.render(); and the html file is as follows: <!DOCTYPE html> <html> <head> <title>SPA Example</title> <!-- <link rel="stylesheet" type="text/css" href="src/css/reset.css" /> <link rel="stylesheet" type="text/css" href="src/css/harmony_compiled.css" /> --> </head> <body class="harmony"> <header> <div class="title">SPA Example</div> </header> <div id="profiles"></div> <script id="profileTemplate" type="text/template"> <div class="profile"> <div class="info"> <div class="intuitId"> <%= intuitId %> </div> <div class="email"> <%= email %> </div> <div class="type"> <%= type %> </div> </div> </div> </script> </body> </html> This gives me an error and the render function isn't invoking properly and the render function is called even before the REST API returns the JSON response. Could anyone please help me to figure out where I went wrong. Any help is highly appreciated Thank you

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  • backbonejs remove anomaly concept

    - by user1537158
    I was building a small app for adding and deleting li from ul using Backbonejs.One of the SO members cymen helped me code it, using that i tailored the code a little.currently if i add one element and delete , it works , but the second time i add an element (to ul) and go to delete it , i get Uncaught TypeError: Cannot call method 'remove' of undefined Pasting my code here , HTML : <input type="text" id="name"> <button id="add">Add</button> <ul id="mylist"></ul> JS: $(function(){ var myCollection = Backbone.Collection.extend(); var myView = Backbone.View.extend({ el:$('body'), tagName:'li', initialize : function(e){ this.collection.bind("add",this.render,this); this.collection.bind("remove",this.render,this); }, events:{ 'click #add' : 'addfoo' }, addfoo : function(){ var myname= $('#name').val(); $('#name').val(''); this.collection.add({name:myname}); }, render : function(){ $('#mylist').empty(); this.collection.each(function(model){ console.log("myView"); var remove = new myRemoveView({model:model}); remove.render(); }); } }); var myRemoveView = Backbone.View.extend({ el:$('body'), events:{ 'click .button':'removeFoo' }, removeFoo : function(){ console.log("here"); this.model.collection.remove(this.model); }, render : function(){ console.log("second view"); $('#mylist').append('<li>'+this.model.get('name') + "<button class='button'>"+"delete"+"</button></li>"); return; } }); var view = new myView({collection: new myCollection()}); }); Two things i did not understand : i) in the removeFoo function , we write this.model.collection.remove(this.model) shouldnt this have been this.collection.model.remove , something of that sort ? ii) i add a li to ul , then i delete it , when i add another li (appending to ul works perfect) but this time when i go to delete it throws me the above error : Uncaught TypeError :cannot call method 'remove' of undefined can you please help me figure out these 2 doubts in my code , btw SO member cymen's code works like a charm only my tailored code (above) is giving me errors. SO member cymen's code : JS Fiddle for his code Thank you

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  • Using HTML 5 SessionState to save rendered Page Content

    - by Rick Strahl
    HTML 5 SessionState and LocalStorage are very useful and super easy to use to manage client side state. For building rich client side or SPA style applications it's a vital feature to be able to cache user data as well as HTML content in order to swap pages in and out of the browser's DOM. What might not be so obvious is that you can also use the sessionState and localStorage objects even in classic server rendered HTML applications to provide caching features between pages. These APIs have been around for a long time and are supported by most relatively modern browsers and even all the way back to IE8, so you can use them safely in your Web applications. SessionState and LocalStorage are easy The APIs that make up sessionState and localStorage are very simple. Both object feature the same API interface which  is a simple, string based key value store that has getItem, setItem, removeitem, clear and  key methods. The objects are also pseudo array objects and so can be iterated like an array with  a length property and you have array indexers to set and get values with. Basic usage  for storing and retrieval looks like this (using sessionStorage, but the syntax is the same for localStorage - just switch the objects):// set var lastAccess = new Date().getTime(); if (sessionStorage) sessionStorage.setItem("myapp_time", lastAccess.toString()); // retrieve in another page or on a refresh var time = null; if (sessionStorage) time = sessionStorage.getItem("myapp_time"); if (time) time = new Date(time * 1); else time = new Date(); sessionState stores data that is browser session specific and that has a liftetime of the active browser session or window. Shut down the browser or tab and the storage goes away. localStorage uses the same API interface, but the lifetime of the data is permanently stored in the browsers storage area until deleted via code or by clearing out browser cookies (not the cache). Both sessionStorage and localStorage space is limited. The spec is ambiguous about this - supposedly sessionStorage should allow for unlimited size, but it appears that most WebKit browsers support only 2.5mb for either object. This means you have to be careful what you store especially since other applications might be running on the same domain and also use the storage mechanisms. That said 2.5mb worth of character data is quite a bit and would go a long way. The easiest way to get a feel for how sessionState and localStorage work is to look at a simple example. You can go check out the following example online in Plunker: http://plnkr.co/edit/0ICotzkoPjHaWa70GlRZ?p=preview which looks like this: Plunker is an online HTML/JavaScript editor that lets you write and run Javascript code and similar to JsFiddle, but a bit cleaner to work in IMHO (thanks to John Papa for turning me on to it). The sample has two text boxes with counts that update session/local storage every time you click the related button. The counts are 'cached' in Session and Local storage. The point of these examples is that both counters survive full page reloads, and the LocalStorage counter survives a complete browser shutdown and restart. Go ahead and try it out by clicking the Reload button after updating both counters and then shutting down the browser completely and going back to the same URL (with the same browser). What you should see is that reloads leave both counters intact at the counted values, while a browser restart will leave only the local storage counter intact. The code to deal with the SessionStorage (and LocalStorage not shown here) in the example is isolated into a couple of wrapper methods to simplify the code: function getSessionCount() { var count = 0; if (sessionStorage) { var count = sessionStorage.getItem("ss_count"); count = !count ? 0 : count * 1; } $("#txtSession").val(count); return count; } function setSessionCount(count) { if (sessionStorage) sessionStorage.setItem("ss_count", count.toString()); } These two functions essentially load and store a session counter value. The two key methods used here are: sessionStorage.getItem(key); sessionStorage.setItem(key,stringVal); Note that the value given to setItem and return by getItem has to be a string. If you pass another type you get an error. Don't let that limit you though - you can easily enough store JSON data in a variable so it's quite possible to pass complex objects and store them into a single sessionStorage value:var user = { name: "Rick", id="ricks", level=8 } sessionStorage.setItem("app_user",JSON.stringify(user)); to retrieve it:var user = sessionStorage.getItem("app_user"); if (user) user = JSON.parse(user); Simple! If you're using the Chrome Developer Tools (F12) you can also check out the session and local storage state on the Resource tab:   You can also use this tool to refresh or remove entries from storage. What we just looked at is a purely client side implementation where a couple of counters are stored. For rich client centric AJAX applications sessionStorage and localStorage provide a very nice and simple API to store application state while the application is running. But you can also use these storage mechanisms to manage server centric HTML applications when you combine server rendering with some JavaScript to perform client side data caching. You can both store some state information and data on the client (ie. store a JSON object and carry it forth between server rendered HTML requests) or you can use it for good old HTTP based caching where some rendered HTML is saved and then restored later. Let's look at the latter with a real life example. Why do I need Client-side Page Caching for Server Rendered HTML? I don't know about you, but in a lot of my existing server driven applications I have lists that display a fair amount of data. Typically these lists contain links to then drill down into more specific data either for viewing or editing. You can then click on a link and go off to a detail page that provides more concise content. So far so good. But now you're done with the detail page and need to get back to the list, so you click on a 'bread crumbs trail' or an application level 'back to list' button and… …you end up back at the top of the list - the scroll position, the current selection in some cases even filters conditions - all gone with the wind. You've left behind the state of the list and are starting from scratch in your browsing of the list from the top. Not cool! Sound familiar? This a pretty common scenario with server rendered HTML content where it's so common to display lists to drill into, only to lose state in the process of returning back to the original list. Look at just about any traditional forums application, or even StackOverFlow to see what I mean here. Scroll down a bit to look at a post or entry, drill in then use the bread crumbs or tab to go back… In some cases returning to the top of a list is not a big deal. On StackOverFlow that sort of works because content is turning around so quickly you probably want to actually look at the top posts. Not always though - if you're browsing through a list of search topics you're interested in and drill in there's no way back to that position. Essentially anytime you're actively browsing the items in the list, that's when state becomes important and if it's not handled the user experience can be really disrupting. Content Caching If you're building client centric SPA style applications this is a fairly easy to solve problem - you tend to render the list once and then update the page content to overlay the detail content, only hiding the list temporarily until it's used again later. It's relatively easy to accomplish this simply by hiding content on the page and later making it visible again. But if you use server rendered content, hanging on to all the detail like filters, selections and scroll position is not quite as easy. Or is it??? This is where sessionStorage comes in handy. What if we just save the rendered content of a previous page, and then restore it when we return to this page based on a special flag that tells us to use the cached version? Let's see how we can do this. A real World Use Case Recently my local ISP asked me to help out with updating an ancient classifieds application. They had a very busy, local classifieds app that was originally an ASP classic application. The old app was - wait for it: frames based - and even though I lobbied against it, the decision was made to keep the frames based layout to allow rapid browsing of the hundreds of posts that are made on a daily basis. The primary reason they wanted this was precisely for the ability to quickly browse content item by item. While I personally hate working with Frames, I have to admit that the UI actually works well with the frames layout as long as you're running on a large desktop screen. You can check out the frames based desktop site here: http://classifieds.gorge.net/ However when I rebuilt the app I also added a secondary view that doesn't use frames. The main reason for this of course was for mobile displays which work horribly with frames. So there's a somewhat mobile friendly interface to the interface, which ditches the frames and uses some responsive design tweaking for mobile capable operation: http://classifeds.gorge.net/mobile  (or browse the base url with your browser width under 800px)   Here's what the mobile, non-frames view looks like:   As you can see this means that the list of classifieds posts now is a list and there's a separate page for drilling down into the item. And of course… originally we ran into that usability issue I mentioned earlier where the browse, view detail, go back to the list cycle resulted in lost list state. Originally in mobile mode you scrolled through the list, found an item to look at and drilled in to display the item detail. Then you clicked back to the list and BAM - you've lost your place. Because there are so many items added on a daily basis the full list is never fully loaded, but rather there's a "Load Additional Listings"  entry at the button. Not only did we originally lose our place when coming back to the list, but any 'additionally loaded' items are no longer there because the list was now rendering  as if it was the first page hit. The additional listings, and any filters, the selection of an item all were lost. Major Suckage! Using Client SessionStorage to cache Server Rendered Content To work around this problem I decided to cache the rendered page content from the list in SessionStorage. Anytime the list renders or is updated with Load Additional Listings, the page HTML is cached and stored in Session Storage. Any back links from the detail page or the login or write entry forms then point back to the list page with a back=true query string parameter. If the server side sees this parameter it doesn't render the part of the page that is cached. Instead the client side code retrieves the data from the sessionState cache and simply inserts it into the page. It sounds pretty simple, and the overall the process is really easy, but there are a few gotchas that I'll discuss in a minute. But first let's look at the implementation. Let's start with the server side here because that'll give a quick idea of the doc structure. As I mentioned the server renders data from an ASP.NET MVC view. On the list page when returning to the list page from the display page (or a host of other pages) looks like this: https://classifieds.gorge.net/list?back=True The query string value is a flag, that indicates whether the server should render the HTML. Here's what the top level MVC Razor view for the list page looks like:@model MessageListViewModel @{ ViewBag.Title = "Classified Listing"; bool isBack = !string.IsNullOrEmpty(Request.QueryString["back"]); } <form method="post" action="@Url.Action("list")"> <div id="SizingContainer"> @if (!isBack) { @Html.Partial("List_CommandBar_Partial", Model) <div id="PostItemContainer" class="scrollbox" xstyle="-webkit-overflow-scrolling: touch;"> @Html.Partial("List_Items_Partial", Model) @if (Model.RequireLoadEntry) { <div class="postitem loadpostitems" style="padding: 15px;"> <div id="LoadProgress" class="smallprogressright"></div> <div class="control-progress"> Load additional listings... </div> </div> } </div> } </div> </form> As you can see the query string triggers a conditional block that if set is simply not rendered. The content inside of #SizingContainer basically holds  the entire page's HTML sans the headers and scripts, but including the filter options and menu at the top. In this case this makes good sense - in other situations the fact that the menu or filter options might be dynamically updated might make you only cache the list rather than essentially the entire page. In this particular instance all of the content works and produces the proper result as both the list along with any filter conditions in the form inputs are restored. Ok, let's move on to the client. On the client there are two page level functions that deal with saving and restoring state. Like the counter example I showed earlier, I like to wrap the logic to save and restore values from sessionState into a separate function because they are almost always used in several places.page.saveData = function(id) { if (!sessionStorage) return; var data = { id: id, scroll: $("#PostItemContainer").scrollTop(), html: $("#SizingContainer").html() }; sessionStorage.setItem("list_html",JSON.stringify(data)); }; page.restoreData = function() { if (!sessionStorage) return; var data = sessionStorage.getItem("list_html"); if (!data) return null; return JSON.parse(data); }; The data that is saved is an object which contains an ID which is the selected element when the user clicks and a scroll position. These two values are used to reset the scroll position when the data is used from the cache. Finally the html from the #SizingContainer element is stored, which makes for the bulk of the document's HTML. In this application the HTML captured could be a substantial bit of data. If you recall, I mentioned that the server side code renders a small chunk of data initially and then gets more data if the user reads through the first 50 or so items. The rest of the items retrieved can be rather sizable. Other than the JSON deserialization that's Ok. Since I'm using SessionStorage the storage space has no immediate limits. Next is the core logic to handle saving and restoring the page state. At first though this would seem pretty simple, and in some cases it might be, but as the following code demonstrates there are a few gotchas to watch out for. Here's the relevant code I use to save and restore:$( function() { … var isBack = getUrlEncodedKey("back", location.href); if (isBack) { // remove the back key from URL setUrlEncodedKey("back", "", location.href); var data = page.restoreData(); // restore from sessionState if (!data) { // no data - force redisplay of the server side default list window.location = "list"; return; } $("#SizingContainer").html(data.html); var el = $(".postitem[data-id=" + data.id + "]"); $(".postitem").removeClass("highlight"); el.addClass("highlight"); $("#PostItemContainer").scrollTop(data.scroll); setTimeout(function() { el.removeClass("highlight"); }, 2500); } else if (window.noFrames) page.saveData(null); // save when page loads $("#SizingContainer").on("click", ".postitem", function() { var id = $(this).attr("data-id"); if (!id) return true; if (window.noFrames) page.saveData(id); var contentFrame = window.parent.frames["Content"]; if (contentFrame) contentFrame.location.href = "show/" + id; else window.location.href = "show/" + id; return false; }); … The code starts out by checking for the back query string flag which triggers restoring from the client cache. If cached the cached data structure is read from sessionStorage. It's important here to check if data was returned. If the user had back=true on the querystring but there is no cached data, he likely bookmarked this page or otherwise shut down the browser and came back to this URL. In that case the server didn't render any detail and we have no cached data, so all we can do is redirect to the original default list view using window.location. If we continued the page would render no data - so make sure to always check the cache retrieval result. Always! If there is data the it's loaded and the data.html data is restored back into the document by simply injecting the HTML back into the document's #SizingContainer element:$("#SizingContainer").html(data.html); It's that simple and it's quite quick even with a fully loaded list of additional items and on a phone. The actual HTML data is stored to the cache on every page load initially and then again when the user clicks on an element to navigate to a particular listing. The former ensures that the client cache always has something in it, and the latter updates with additional information for the selected element. For the click handling I use a data-id attribute on the list item (.postitem) in the list and retrieve the id from that. That id is then used to navigate to the actual entry as well as storing that Id value in the saved cached data. The id is used to reset the selection by searching for the data-id value in the restored elements. The overall process of this save/restore process is pretty straight forward and it doesn't require a bunch of code, yet it yields a huge improvement in the usability of the site on mobile devices (or anybody who uses the non-frames view). Some things to watch out for As easy as it conceptually seems to simply store and retrieve cached content, you have to be quite aware what type of content you are caching. The code above is all that's specific to cache/restore cycle and it works, but it took a few tweaks to the rest of the script code and server code to make it all work. There were a few gotchas that weren't immediately obvious. Here are a few things to pay attention to: Event Handling Logic Timing of manipulating DOM events Inline Script Code Bookmarking to the Cache Url when no cache exists Do you have inline script code in your HTML? That script code isn't going to run if you restore from cache and simply assign or it may not run at the time you think it would normally in the DOM rendering cycle. JavaScript Event Hookups The biggest issue I ran into with this approach almost immediately is that originally I had various static event handlers hooked up to various UI elements that are now cached. If you have an event handler like:$("#btnSearch").click( function() {…}); that works fine when the page loads with server rendered HTML, but that code breaks when you now load the HTML from cache. Why? Because the elements you're trying to hook those events to may not actually be there - yet. Luckily there's an easy workaround for this by using deferred events. With jQuery you can use the .on() event handler instead:$("#SelectionContainer").on("click","#btnSearch", function() {…}); which monitors a parent element for the events and checks for the inner selector elements to handle events on. This effectively defers to runtime event binding, so as more items are added to the document bindings still work. For any cached content use deferred events. Timing of manipulating DOM Elements Along the same lines make sure that your DOM manipulation code follows the code that loads the cached content into the page so that you don't manipulate DOM elements that don't exist just yet. Ideally you'll want to check for the condition to restore cached content towards the top of your script code, but that can be tricky if you have components or other logic that might not all run in a straight line. Inline Script Code Here's another small problem I ran into: I use a DateTime Picker widget I built a while back that relies on the jQuery date time picker. I also created a helper function that allows keyboard date navigation into it that uses JavaScript logic. Because MVC's limited 'object model' the only way to embed widget content into the page is through inline script. This code broken when I inserted the cached HTML into the page because the script code was not available when the component actually got injected into the page. As the last bullet - it's a matter of timing. There's no good work around for this - in my case I pulled out the jQuery date picker and relied on native <input type="date" /> logic instead - a better choice these days anyway, especially since this view is meant to be primarily to serve mobile devices which actually support date input through the browser (unlike desktop browsers of which only WebKit seems to support it). Bookmarking Cached Urls When you cache HTML content you have to make a decision whether you cache on the client and also not render that same content on the server. In the Classifieds app I didn't render server side content so if the user comes to the page with back=True and there is no cached content I have to a have a Plan B. Typically this happens when somebody ends up bookmarking the back URL. The easiest and safest solution for this scenario is to ALWAYS check the cache result to make sure it exists and if not have a safe URL to go back to - in this case to the plain uncached list URL which amounts to effectively redirecting. This seems really obvious in hindsight, but it's easy to overlook and not see a problem until much later, when it's not obvious at all why the page is not rendering anything. Don't use <body> to replace Content Since we're practically replacing all the HTML in the page it may seem tempting to simply replace the HTML content of the <body> tag. Don't. The body tag usually contains key things that should stay in the page and be there when it loads. Specifically script tags and elements and possibly other embedded content. It's best to create a top level DOM element specifically as a placeholder container for your cached content and wrap just around the actual content you want to replace. In the app above the #SizingContainer is that container. Other Approaches The approach I've used for this application is kind of specific to the existing server rendered application we're running and so it's just one approach you can take with caching. However for server rendered content caching this is a pattern I've used in a few apps to retrofit some client caching into list displays. In this application I took the path of least resistance to the existing server rendering logic. Here are a few other ways that come to mind: Using Partial HTML Rendering via AJAXInstead of rendering the page initially on the server, the page would load empty and the client would render the UI by retrieving the respective HTML and embedding it into the page from a Partial View. This effectively makes the initial rendering and the cached rendering logic identical and removes the server having to decide whether this request needs to be rendered or not (ie. not checking for a back=true switch). All the logic related to caching is made on the client in this case. Using JSON Data and Client RenderingThe hardcore client option is to do the whole UI SPA style and pull data from the server and then use client rendering or databinding to pull the data down and render using templates or client side databinding with knockout/angular et al. As with the Partial Rendering approach the advantage is that there's no difference in the logic between pulling the data from cache or rendering from scratch other than the initial check for the cache request. Of course if the app is a  full on SPA app, then caching may not be required even - the list could just stay in memory and be hidden and reactivated. I'm sure there are a number of other ways this can be handled as well especially using  AJAX. AJAX rendering might simplify the logic, but it also complicates search engine optimization since there's no content loaded initially. So there are always tradeoffs and it's important to look at all angles before deciding on any sort of caching solution in general. State of the Session SessionState and LocalStorage are easy to use in client code and can be integrated even with server centric applications to provide nice caching features of content and data. In this post I've shown a very specific scenario of storing HTML content for the purpose of remembering list view data and state and making the browsing experience for lists a bit more friendly, especially if there's dynamically loaded content involved. If you haven't played with sessionStorage or localStorage I encourage you to give it a try. There's a lot of cool stuff that you can do with this beyond the specific scenario I've covered here… Resources Overview of localStorage (also applies to sessionStorage) Web Storage Compatibility Modernizr Test Suite© Rick Strahl, West Wind Technologies, 2005-2013Posted in JavaScript  HTML5  ASP.NET  MVC   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • GTX 280 purple snow on bootup, card works without drivers

    - by Brokar
    i have owned a ASUS GTX280 for 3 years now. The card has been great all along but i started having problems 10 days ago. I was playing Diablo 3 for 1 week on max settings no problems, then suddenly my display kept getting some weird purple/colours as soon as i booted and logged into windows. Went into safe mode, updated drivers and it kept crashing. Formatted PC, fresh windows install with new WHQL drivers again same problem. Uninstalled nvidia drivers and pc has been running great for 4 days now, ofcourse i cannot run games but everything works on 1680x1050 resolution and i can browse internet,watch movies and use my PC for everything but gaming. As soon as i install nvidia drivers PC won't boot. I only wanna game a few hours a week (very busy program with school this month so it might be a blessing that i cannot game) and i would love it if i could keep the card. I am looking to upgrde later on when i will have time for gaming but i wonder if i could still use the card somehow with different/new drivers (tried older drivers that came with the card on a CD aswell) tldr: PC works fine with no nvidia drivers (apart from gaming ofc). Once i install WHQL drivers or older ones, cannot even log into windows. Fix?

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  • how does openvpn decide which interface to get IP addrs from

    - by bkrupa
    Using ubuntu 10.04 on both ends. We have a client and server machine on the SAME network attempting to make a vpn connection. We use the config files from here and made minimal changes. The server and client start and seem to connect without any trouble. The server looks like: Wed Feb 23 22:13:22 2011 MULTI: multi_create_instance called Wed Feb 23 22:13:22 2011 192.168.1.55:47166 Re-using SSL/TLS context Wed Feb 23 22:13:22 2011 192.168.1.55:47166 LZO compression initialized Wed Feb 23 22:13:22 2011 192.168.1.55:47166 Control Channel MTU parms [ L:1574 D:138 EF:38 EB:0 ET:0 EL:0 ] Wed Feb 23 22:13:22 2011 192.168.1.55:47166 Data Channel MTU parms [ L:1574 D:1450 EF:42 EB:135 ET:32 EL:0 AF:3/1 ] Wed Feb 23 22:13:22 2011 192.168.1.55:47166 Local Options hash (VER=V4): 'f7df56b8' Wed Feb 23 22:13:22 2011 192.168.1.55:47166 Expected Remote Options hash (VER=V4): 'd79ca330' Wed Feb 23 22:13:22 2011 192.168.1.55:47166 TLS: Initial packet from 192.168.1.55:47166, sid=69112e42 5458135b *...* Wed Feb 23 22:13:22 2011 192.168.1.55:47166 Control Channel: TLSv1, cipher TLSv1/SSLv3 DHE-RSA-AES256-SHA, 1024 bit RSA Wed Feb 23 22:13:22 2011 192.168.1.55:47166 [client1] Peer Connection Initiated with 192.168.1.55:47166 On the client side the connection looks like: Wed Feb 23 22:20:07 2011 [server] Peer Connection Initiated with [AF_INET]192.168.1.41:1194 Wed Feb 23 22:20:10 2011 SENT CONTROL [server]: 'PUSH_REQUEST' (status=1) Wed Feb 23 22:20:10 2011 PUSH: Received control message: 'PUSH_REPLY,route-gateway 10.8.0.4,ping 10,ping-restart 120,ifconfig 10.8.0.50 255.255.255.0' ... Wed Feb 23 22:20:10 2011 /sbin/ifconfig tap0 10.8.0.50 netmask 255.255.255.0 mtu 1500 broadcast 10.8.0.255 Wed Feb 23 22:20:10 2011 Initialization Sequence Completed The openvpn server has been configured to assign ip addresses in the range 10.8.0.* and the client has been given 10.8.0.50. When I run the following nmap from the client: Starting Nmap 5.00 ( http://nmap.org ) at 2011-02-23 22:04 EST Host 10.8.0.50 is up (0.00047s latency). Nmap done: 256 IP addresses (1 host up) scanned in 30.34 seconds Host 192.168.1.1 is up (0.0025s latency). Host 192.168.1.18 is up (0.074s latency). Host 192.168.1.41 is up (0.0024s latency). Host 192.168.1.55 is up (0.00018s latency). Nmap done: 256 IP addresses (4 hosts up) scanned in 6.33 seconds If I run an nmap from the server on 10.8.0.* I get nothing. If the client has two interfaces (wireless and tap device) when you look for a certain ip address, how does it decide which interface to connect on? edit I am trying to set up a vpn so that I can connect to my home network from a remote network. It seems like openvpn is connecting but none of the computers on my home network appear as network machines even after the connection is "Established". Stripped versions of the client and server config files are posted below. Thanks for any help you can offer. server.conf port 1194 proto udp dev tap ca /etc/openvpn/easy-rsa/keys/ca.crt cert /etc/openvpn/easy-rsa/keys/server.crt key /etc/openvpn/easy-rsa/keys/server.key # This file should be kept secret dh /etc/openvpn/easy-rsa/keys/dh1024.pem ifconfig-pool-persist ipp.txt server-bridge 10.8.0.4 255.255.255.0 10.8.0.50 10.8.0.100 keepalive 10 120 comp-lzo persist-key persist-tun status openvpn-status.log verb 3 client.conf client dev tap dev-node tap0901 proto udp remote ********** 1194 resolv-retry infinite nobind persist-key persist-tun ca ca.crt cert client1.crt key client1.key comp-lzo verb 3 one other thing that might be helpful, I tried to connect using the openvpn gui for windows and the connection stalls out on "obtaining configuration" and the bar just scrolls forever.

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  • Why a 10 years old software still is so slow even today?

    - by Cawas
    I just noted this question due to a game (which happens to be Diablo 2), but the matter of fact is: why is my brand new mac book pro, made in 2009 with latest technology (tho it's the cheapest one) can't rival my computer which used to run this much faster back in 2000? Really, it was much faster on my AMD K6 450 back in those days, and I could even run two clients at same time with no slow down. I've always had the feeling this machine was slow, but this is a very odd way to attest it. Granted, the machine is smaller, runs on wifi and "boots" way faster thanks to sleep mode. But other than that, what have we evolved after all?! I'm pretty sure this shouldn't be graphical card's fault. Sure if I buy latest technology it will run fast, and probably most people here can confirm this and won't even understand my question. But the thing is, all the hardware is supposedly much faster and better than the stuff from 10 years ago. The software and operating system became more complex, but also more well refined. Now I'm trying a piece of software that is actually 10 years old and it's not getting any better results! Why?

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  • Openvpn issue with linux

    - by catsy
    So I've tried to setup openvpn, I followed some guide but it's stuck att "initialization sequence completed" with no connection and I can't find any working solution... here's the log: $Sun Sep 23 19:14:32 2012 OpenVPN 2.1.0 i486-pc-linux-gnu [SSL] [LZO2] [EPOLL] [PKCS11] [MH] [PF_INET6] [eurephia] built on Jul 20 2010 Enter Auth Username:pumpedup Enter Auth Password: Sun Sep 23 19:14:37 2012 WARNING: No server certificate verification method has been enabled. See http://openvpn.net/howto.html#mitm for more info. Sun Sep 23 19:14:37 2012 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables Sun Sep 23 19:14:37 2012 LZO compression initialized Sun Sep 23 19:14:37 2012 Control Channel MTU parms [ L:1542 D:138 EF:38 EB:0 ET:0 EL:0 ] Sun Sep 23 19:14:38 2012 Data Channel MTU parms [ L:1542 D:1450 EF:42 EB:135 ET:0 EL:0 AF:3/1 ] Sun Sep 23 19:14:38 2012 Local Options hash (VER=V4): '41690919' Sun Sep 23 19:14:38 2012 Expected Remote Options hash (VER=V4): '530fdded' Sun Sep 23 19:14:38 2012 Socket Buffers: R=[163840-131072] S=[163840-131072] Sun Sep 23 19:14:38 2012 UDPv4 link local: [undef] Sun Sep 23 19:14:38 2012 UDPv4 link remote: [AF_INET]192.162.102.162:1194 Sun Sep 23 19:14:38 2012 TLS: Initial packet from [AF_INET]192.162.102.162:1194, sid=87a95723 a6d7b7f9 Sun Sep 23 19:14:38 2012 WARNING: this configuration may cache passwords in memory -- use the auth-nocache option to prevent this Sun Sep 23 19:14:38 2012 VERIFY OK: depth=1, /C=NV/ST=NV/L=nVPN/O=nVpn/CN=nVpn_CA/[email protected] Sun Sep 23 19:14:38 2012 VERIFY OK: depth=0, /C=NV/ST=NV/L=nVPN/O=nVpn/CN=server/[email protected] Sun Sep 23 19:14:39 2012 WARNING: 'link-mtu' is used inconsistently, local='link-mtu 1542', remote='link-mtu 6042' Sun Sep 23 19:14:39 2012 WARNING: 'tun-mtu' is used inconsistently, local='tun-mtu 1500', remote='tun-mtu 6000' Sun Sep 23 19:14:39 2012 Data Channel Encrypt: Cipher 'BF-CBC' initialized with 128 bit key Sun Sep 23 19:14:39 2012 Data Channel Encrypt: Using 160 bit message hash 'SHA1' for HMAC authentication Sun Sep 23 19:14:39 2012 Data Channel Decrypt: Cipher 'BF-CBC' initialized with 128 bit key Sun Sep 23 19:14:39 2012 Data Channel Decrypt: Using 160 bit message hash 'SHA1' for HMAC authentication Sun Sep 23 19:14:39 2012 Control Channel: TLSv1, cipher TLSv1/SSLv3 DHE-RSA-AES256-SHA, 1024 bit RSA Sun Sep 23 19:14:39 2012 [server] Peer Connection Initiated with [AF_INET]192.162.102.162:1194 Sun Sep 23 19:14:41 2012 SENT CONTROL [server]: 'PUSH_REQUEST' (status=1) Sun Sep 23 19:14:41 2012 PUSH: Received control message: 'PUSH_REPLY,redirect-gateway def1,dhcp-option DNS 8.8.8.8,dhcp-option DNS 8.8.8.8,route 10.102.162.1,topology net30,ping 10,ping-restart 120,ifconfig 10.102.162.6 10.102.162.5' Sun Sep 23 19:14:41 2012 OPTIONS IMPORT: timers and/or timeouts modified Sun Sep 23 19:14:41 2012 OPTIONS IMPORT: --ifconfig/up options modified Sun Sep 23 19:14:41 2012 OPTIONS IMPORT: route options modified Sun Sep 23 19:14:41 2012 OPTIONS IMPORT: --ip-win32 and/or --dhcp-option options modified Sun Sep 23 19:14:41 2012 ROUTE default_gateway=10.0.2.2 Sun Sep 23 19:14:41 2012 TUN/TAP device tun0 opened Sun Sep 23 19:14:41 2012 TUN/TAP TX queue length set to 100 Sun Sep 23 19:14:41 2012 /sbin/ifconfig tun0 10.102.162.6 pointopoint 10.102.162.5 mtu 1500 Sun Sep 23 19:14:41 2012 /sbin/route add -net 192.162.102.162 netmask 255.255.255.255 gw 10.0.2.2 Sun Sep 23 19:14:41 2012 /sbin/route add -net 0.0.0.0 netmask 128.0.0.0 gw 10.102.162.5 Sun Sep 23 19:14:41 2012 /sbin/route add -net 128.0.0.0 netmask 128.0.0.0 gw 10.102.162.5 Sun Sep 23 19:14:41 2012 /sbin/route add -net 10.102.162.1 netmask 255.255.255.255 gw 10.102.162.5 Sun Sep 23 19:14:41 2012 Initialization Sequence Completed

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  • Performance decrease in every game and application

    - by Márk Vincze
    When I start a game, initially it runs smoothly, but after a couple of minutes, the performance gradually decreases to the point of being unplayable (1-2 FPS). The sound also starts to lag at this point. This does not happen every time I start my PC, usually exiting the game, rebooting, then starting the game again solves the problem, and I can play with perfect FPS for as long as I want. I could not find any deterministic reason when this happens and when doesn't. It happens in every game I tried (SWTOR, Diablo 3, Skyrim), and not even games, but simple applications like a browser or the Control Panel can get unusably slow. This is a brand new PC I bought three months ago, and this problem occurs since the first day I've been using it. Could you provide any advice how to further diagnose the problem? I tried to reinstall Windows, and tried different video card drivers, but it did not help. It would be important to know whether this is a hardware or software problem, because I can use the warranty if it is a hardware issue. (I did not want to return the PC yet, because I can't reproduce the issue deterministically.) Spec of the pc: Motherboard: ASROCK H61M-HVS CPU: INTEL Core i3-2120 3.30GHz 1155 BOX Memory: KINGMAX 4096MB DDR3 1333MHz KIT Video card: GIGABYTE GV-R685OC-1GD HD6850 1GB GDDR5 PCIE HDD: SEAGATE 500GB Barracuda 7200rpm 16MB SATA3 ST500DM002 I am using Windows 7 64 bit. Thanks a lot in advance!

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  • CodePlex Daily Summary for Thursday, April 08, 2010

    CodePlex Daily Summary for Thursday, April 08, 2010New ProjectsBackUpAnyWhere: BackUpAnyWhereCustomFormbyEndUser: 在项目开发中,经常遇到不同的用户对同一报表有不同要求的情况,有时甚至用户需要从头生成一个报表,在以前可能使用第三方的开发工具来实现。在SQL Server2005中,通过使用Reporting Services可以使最终用户不通过编码,只要了解数据结构就能自行编辑报表。本例使用Adventur...DbExecutor - linq based database executor: IEnumerable based database reader. (linq like primitive sql executor)DeepZoomRenderingPack: A collection of libraries and plug-ins architecture that turns various files (like PDF, PS, etc.) into a "Visual" representation that the DeepZoom ...DotNetNuke Russian Language packs: DNNRussianLP - DotNetNuke Russian Language pack. F# Refactor: Deisgned to bring Code Refactoring capabilities to the F# Language in Visual Studio 2010. Invocando WebService e Site HTTP dinamicamente com HTTPWebRequest C#: Invocando Site HTTP e WebService dinamicamente com HTTPWebRequest Passando o SoapAction e Envelope XML Escrito em C# www.biztalkbrasil.c...Jitbit WYSWYG BBCode Editor: "Jitbit WYSIWYG-BBCode" is a browser-based JavaScript-powered WYSIWYG BBCode editorMRDS Services for Phidgets: MRDS (Microsoft Robotics Developer Studio) Services for Phidgets provides additional services for Phidgets sensors and controllers that are not inc...MSBuild Addin: This tool is a simple addin for VisualStudio 2008 used in association with Microsoft MSBuild. It allows you to run MSBuild directly inside Visual S...NISHIL-BizTalk Custom Eventlog Functiod: While testing our maps at times when it fails we cant trace it because we don’t know what the output of the functiods are. Normally in a single ma...Northest GNSG: Supinfo B3C Paris Northest University project. Galego, Neveu, Simon, Geissmann.Oily: Composite application project for oil parameters. It's developed in C#Outlook.Utility: The MSDN article Outlook Customization for Integrating with Enterprise Applications at http://msdn.microsoft.com/en-us/library/Aa479345 has quite a...Particle Plot Pivot: Scan select particle physics experiment web sites for plots and generate a Pivot display for easy browsing.project tca: project tca - translating chat application. Satisfyr: A new way of performing assertions on tests so that they remain agnostic to the underlying test framework, and leverage .NET built-in lambda syntax.sejce2008: jce se course wiki and projects linksSGB Controls: SGB Controls is a set of standard .net controls that include a number of enhancements to make life easier for the developer. These controls incl...Syringe: Syringe is a lightweight service container and dependency injection library designed for use with ASP.NET MVC2. Supported features: Dependency inj...topicbox: topicboxUr-Index: Ur-Index makes it a lot easier to create onomastic indexes for books in pdf format.VietGeeks ZohoDocApis: Implement .NET Zoho Document Apis library to help developer can intergrate Zoho Docs easy with their websitesWebometrics Dashboard: Webometrics Dashboardwebpress: It is a WebBased CMS and Blog platform.WPF Ink Canvas Toolbar: WPF Ink Canvas Toolbar makes it easy for WPF developers to use pen input in TabletPC or UMPC applications. The WPF InkCanvas control has drawing, e...WS-TMS: WS GISG HTT TMSNew ReleasesBatterySaver: Version 1.0: Fixed battery increase/decrease events not firing Fixed memory corruption error Added working set trimming (used very sparingly) Fixed poorly rende...Chargify.NET: Chargify.NET 0.65: Added in Transactions, Subscription Re-activation, and finally XML documentation (which has been missing in the previous releases).DbExecutor - linq based database executor: DbExecutor ver.1.0.0.1: renameDotNetNuke Russian Language packs: Russian Language Pack for DotNetNuke 04.09.02: Russian Language Pack for DotNetNuke 04.09.02Encrypted Notes: Encrypted Notes 1.6.3: This is the latest version of Encrypted Notes (1.6.3), with general improvements. It has an installer that will create a directory 'CPascoe' in My ...Invocando WebService e Site HTTP dinamicamente com HTTPWebRequest C#: Código projeto CallSiteHTTP: Código escrito em C#.NET 2.0 - VS2005 Contem: Solution completa(código e executável) XML de configuração - Config.xml ...Jitbit WYSWYG BBCode Editor: Main package: Contains the JS-file, CSS-file and a sample.Live Writer Picasa Plugin: Live Writer Picasa Plugin 1.1.0: Changelog Communication with Picasa Web Albums is done directly via HTTP now (v1.0.0 used Google's GData .NET Libraries) The plugin can search fo...MRDS Services for Phidgets: Phidgets for RDS 2008 R3: First Beta Release This ZIP file contains a web page called Readme_CodePlex.html that explains how to install the RDS Phidgets services for RDS 200...MSBuild Addin: MsBuildAddin-v1.0.0: Initial versionMSBuild Addin: MsBuildAddin-v1.0.0-src.zip: Initial versionOutlook.Utility: Outlook.Utility v1: I have used most of the code in previous projects and seems to be quite stable. Of course the point of open sourcing this is so this project is use...Scrum Dashboard: Scrum Dashboard v3 Alpha 1: Scrum Dashboard v3 is targeting .NET 4, TFS 2010 and the brand new Scrum for Team System v3 process templates. Most of the code has been rewritten ...SharePoint Labs: SPLab4004A-FRA-Level100: SPLab4004A-FRA-Level100 This SharePoint Lab will teach you the 4th best practice you should apply when writing code with the SharePoint API. Lab La...SharePoint Labs: SPLab5012A-FRA-Level100: SPLab5012A-FRA-Level100 This SharePoint Lab will teach you how to provision a new welcome page (how to change and rename the default.aspx page) on ...Shweet: SharePoint 2010 Team Messaging built with Pex: Shweet Source Code: Although the latest version pex and moles used with this project is not available, we thought it would be useful to provide a download to the source.Syringe: Syringe 1.0: Features Dependency injection on properties of services in container Dependency injection on constructors of services in container ASP.Net Mvc ...Text to HTML: 0.4.1.0: Cambios de la versiónOptimización del código de exportación reduciendo el código. Cambio en el icono de exportación. Añadido menú Seleccionar t...VsTortoise - a TortoiseSVN add-in for Microsoft Visual Studio: VsTortoise Build 23: Build 23 Fix: Executing "Blame" through the Solution Explorer on a file opens TortoiseMerge rather than TortoiseBlame. Build 22 (beta) New: Visua...WPF Ink Canvas Toolbar: WPF Ink Canvas Toolbar 1.0: First release - included custom colour selectionMost Popular ProjectsRawrWBFS ManagerMicrosoft SQL Server Product Samples: DatabaseASP.NET Ajax LibrarySilverlight ToolkitAJAX Control ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesFacebook Developer ToolkitMost Active ProjectsGraffiti CMSnopCommerce. Open Source online shop e-commerce solution.RawrShweet: SharePoint 2010 Team Messaging built with Pexpatterns & practices – Enterprise LibraryAcadsysAutoPocoIonics Isapi Rewrite FilterNcqrs Framework - The CQRS framework for .NETFarseer Physics Engine

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  • CodePlex Daily Summary for Thursday, April 15, 2010

    CodePlex Daily Summary for Thursday, April 15, 2010New ProjectsApplication Logging Repository (ALR): The ALR is a light-weight logging framework that allows applications to log events and exceptions to a central repository.Arkane.FileProperties.DSS: Arkane.FileProperties.Dss is a library for parsing the file header of a .DSS file (as used by Olympus digital dictaphone systems) to obtain time, v...B in conTrol project: This project enables controling log-in and locking your workstation automatically, identifyng you bluetooth.DarkBook: DarkBook is a personal library project.Direct2D for Microsoft .Net: Direct2D, DirectWrite and Windows Imaging wrappers for .Net. This library allows to access Direct2D, DirectWrite and Windows Imaging Windows API f...DJ Ware: DJ Ware is an extensible music player with plugin support and innovative features to organize and explore music files. It is developed with C#, WPF...gpsMe: gpsMe is a Windows Mobile 6.x mapping solution allowing to place the user on a personnalized map. The screen requirements are VGA or WVGA but, you ...jErrorLog: jErrorLog is an error logging component for use in DotNet 2.0 or later applications. It can log error messages to any of the following: database, e...KEMET_API: Java Library (open - source). This library is a help to study egyptian hieroglyphs.Meadow: A web site project for a Swedish floorball team called Slackers. Home page built with ASP.NET 2.0, ASP.NET AJAX and SQL Server 2005.Mustang Math: Mustang Math makes it easier for young children to practice basic math facts on the computer. No keyboard or mouse required - just say the answer!...Net.Formats.oEmbed: oEmbed format implementation in c#. oEmbed is a format for allowing an embedded representation of a URL on third party sites. The simple API allows...Normlize O/R Mapper: Open source O/RM tool that participates with traditional inheritance object models as well as Hibernate/nHibernate style class shells. As I have t...N-Twill Twitter Client for VB.NET: Proyecto de cliente twitter hecho con la libreria TwitterVB2 y hecho en VB.net 2008.SIQM: Spatial Information Quality Management Toolset TIMETABLEASY Web: Under developmentTweetSharp: TweetSharp is a complete .NET library for micro-blogging platforms that allows you to write short and sweet expressions that fly to Twitter, Yammer...UISandbox: UISandbox is a sample C# source code showing how to deal with plugins requiring sandbox, when those plugins must interact with WPF application inte...WinForm SharePoint Web Part Manager: The SharePoint Web Part Manager is a WinForm tool using the SharePoint object model that enables developers and power users to add, update, delete,...WoW Character Viewer: View your World of Warcraft character (or anyone else's character), using this application. Written using Visual Basic Express 2008, then ported t...Xrns2XMod: Xrns2XMod converts from Renoise format (xrns) to mod or xm, which are more compatible formats playable from xmplay or vlc.New ReleasesArkane.FileProperties.DSS: 1.0 stable release: Executables and merge module for 1.0. (See documentation.)Bluetooth Radar: Version 2.0: Add IrDA reference for Bluetooth sending using Obex Add Project icon Add Bluetooth detection mode (Auto close application is there is no blueto...BUtil: BUtil 5.0 Alpha: Backup tasks adding.... in progressChronos WPF: Chronos v1.0 RC 1: Chronos v1.0 RC 1. Development will be feature frozen after this release, only bug fixes will be allowed. Updated nRoute assembly to v0.4 (http:...clipShow: Version 2.5: Release that addresses the canonical syntax issues in search discoverd by Tschachim (thanks again!). Also, the play list and play all menu items s...DarkBook: DarkBook alpha: Hi, here comes the alpha version of Darkbook. It has all the functions already but is still in developing. I hope it's helpful for you, at least it...DirectQ: Release 1.8.3a: Improvements to 1.8.2, which will be shortly be removed. This replaces the original 1.8.3 release from earlier today which had some late-breaking ...Effect Custom Tool for Visual Studio: Effect Custom Tool v1.1: Effect Custom Tool for Visual Studio is a visual studio 2008 extension that helps you generate c# classes from effect (*.fx) files for use with Xna...Folder Bookmarks: Folder Bookmarks 1.4.3: This is the latest version of Folder Bookmarks (1.4.3), with general improvements. It has an installer - it will create a directory 'CPascoe' in My...gpsMe: gpsMe v0.3: Required Hardware Windows Mobile 6 .Net Compact Framework 3.5 integrated gps device VGA or WVGA screen (normally works on others)IST435: Lab 4 - Enterprise Level CMS with DotNetNuke: Lab 4 - Enterprise Level CMS with DotNetNukeThis is the "starter kit" that you must base your Lab 4 on. This lab must be completed in-class.Mouse Jiggler: MouseJiggle-1.1: 1.1 release of Mouse Jiggler, now with x64 compatibility and the ability to start jiggling on run with the --jiggle or -j command-line switch.Mustang Math: MustangMath.exe: This is a quick and dirty "0.1" prototype to demonstrate the speech recognition idea. It starts asking you questions automatically on launch and k...MvcContrib: a Codeplex Foundation project: 2.0.36.0 for MVC2 (RTW): Please see the Change Log for a complete list of changes. MVC BootCamp Description of the releases: MvcContrib.Release.zip MvcContrib.dll MvcC...Nito.LINQ: Beta (v0.3): New features for this release: Several new supported platforms (see below). PDBs that are source-indexed to the appropriate CodePlex changeset. ...OpenIdPortableArea: 0.1.0.2 OpenIdPortableArea: OpenIdPortableArea.Release: DotNetOpenAuth.dll DotNetOpenAuth.xml MvcContrib.dll MvcContrib.xml OpenIdPortableArea.dll OpenIdPortableAre...PokeIn Comet Ajax Library: PokeIn Sample with Library v0.2: New version of PokeIn library with sample. v0.2 There are new features in this release and no bug detected yet.Project Tru Tiên: Elements-test V1-fix (v2): Là EL test được fix tiếp theo bản fix V1, tạm gọi đây là bản fix V2 của ELtest Trong bản fix này EL được fix thêm vụ Quest, Quest chỉnh sửa đúng t...Rule 18 - Love your clipboard: Rule 18: This is the third public beta for the first version of Rule 18. This version has been updated to support Visual Studio 2010 RTM and .NET 4.0 RTM. ...SevenZipSharp: SevenZipSharp 0.62: Added: Extraction from SFX archives. Now it is possible to unrar RAR self-extractors, unzip ZIP self-extractors, etc. Extraction from DOC, XLS, (...SharePoint Labs: SPLab3001A-FRA-Level200: SPLab3001A-FRA-Level200 This SharePoint Lab will teach the persistence object layer that SharePoint uses to centraly store configuration data and o...TTXPathNavigator: TTXPathNavigator for VS2010: Version for Visual Studio 2010turing machine simulator: SDS: SDS documentVecDraw: VecDraw_0.2.25: Alpha release for test purposesWinForm SharePoint Web Part Manager: Beta 1: First release of the WinForm SharePoitn web part manager toolXrns2XMod: Xrns2XMod 0.5.1: Mod and XM conversion format - No sample data conversion at momentZip Solution: ZipSolution 5.3: Features: 1. Added WaitMsec for visual studio support with getting access to files in post build event; 2. Added ShowTextInToolbars to app.config ...Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesPHPExcelpatterns & practices – Enterprise LibraryMost Active ProjectsRawrpatterns & practices – Enterprise LibraryGMap.NET - Great Maps for Windows Forms & PresentationFarseer Physics EngineIonics Isapi Rewrite FilterNB_Store - Free DotNetNuke Ecommerce Catalog ModuleBlogEngine.NETjQuery Library for SharePoint Web ServicesDotRasFacebook Developer Toolkit

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  • C#: Does an IDisposable in a Halted Iterator Dispose?

    - by James Michael Hare
    If that sounds confusing, let me give you an example. Let's say you expose a method to read a database of products, and instead of returning a List<Product> you return an IEnumerable<Product> in iterator form (yield return). This accomplishes several good things: The IDataReader is not passed out of the Data Access Layer which prevents abstraction leak and resource leak potentials. You don't need to construct a full List<Product> in memory (which could be very big) if you just want to forward iterate once. If you only want to consume up to a certain point in the list, you won't incur the database cost of looking up the other items. This could give us an example like: 1: // a sample data access object class to do standard CRUD operations. 2: public class ProductDao 3: { 4: private DbProviderFactory _factory = SqlClientFactory.Instance 5:  6: // a method that would retrieve all available products 7: public IEnumerable<Product> GetAvailableProducts() 8: { 9: // must create the connection 10: using (var con = _factory.CreateConnection()) 11: { 12: con.ConnectionString = _productsConnectionString; 13: con.Open(); 14:  15: // create the command 16: using (var cmd = _factory.CreateCommand()) 17: { 18: cmd.Connection = con; 19: cmd.CommandText = _getAllProductsStoredProc; 20: cmd.CommandType = CommandType.StoredProcedure; 21:  22: // get a reader and pass back all results 23: using (var reader = cmd.ExecuteReader()) 24: { 25: while(reader.Read()) 26: { 27: yield return new Product 28: { 29: Name = reader["product_name"].ToString(), 30: ... 31: }; 32: } 33: } 34: } 35: } 36: } 37: } The database details themselves are irrelevant. I will say, though, that I'm a big fan of using the System.Data.Common classes instead of your provider specific counterparts directly (SqlCommand, OracleCommand, etc). This lets you mock your data sources easily in unit testing and also allows you to swap out your provider in one line of code. In fact, one of the shared components I'm most proud of implementing was our group's DatabaseUtility library that simplifies all the database access above into one line of code in a thread-safe and provider-neutral way. I went with my own flavor instead of the EL due to the fact I didn't want to force internal company consumers to use the EL if they didn't want to, and it made it easy to allow them to mock their database for unit testing by providing a MockCommand, MockConnection, etc that followed the System.Data.Common model. One of these days I'll blog on that if anyone's interested. Regardless, you often have situations like the above where you are consuming and iterating through a resource that must be closed once you are finished iterating. For the reasons stated above, I didn't want to return IDataReader (that would force them to remember to Dispose it), and I didn't want to return List<Product> (that would force them to hold all products in memory) -- but the first time I wrote this, I was worried. What if you never consume the last item and exit the loop? Are the reader, command, and connection all disposed correctly? Of course, I was 99.999999% sure the creators of C# had already thought of this and taken care of it, but inspection in Reflector was difficult due to the nature of the state machines yield return generates, so I decided to try a quick example program to verify whether or not Dispose() will be called when an iterator is broken from outside the iterator itself -- i.e. before the iterator reports there are no more items. So I wrote a quick Sequencer class with a Dispose() method and an iterator for it. Yes, it is COMPLETELY contrived: 1: // A disposable sequence of int -- yes this is completely contrived... 2: internal class Sequencer : IDisposable 3: { 4: private int _i = 0; 5: private readonly object _mutex = new object(); 6:  7: // Constructs an int sequence. 8: public Sequencer(int start) 9: { 10: _i = start; 11: } 12:  13: // Gets the next integer 14: public int GetNext() 15: { 16: lock (_mutex) 17: { 18: return _i++; 19: } 20: } 21:  22: // Dispose the sequence of integers. 23: public void Dispose() 24: { 25: // force output immediately (flush the buffer) 26: Console.WriteLine("Disposed with last sequence number of {0}!", _i); 27: Console.Out.Flush(); 28: } 29: } And then I created a generator (infinite-loop iterator) that did the using block for auto-Disposal: 1: // simply defines an extension method off of an int to start a sequence 2: public static class SequencerExtensions 3: { 4: // generates an infinite sequence starting at the specified number 5: public static IEnumerable<int> GetSequence(this int starter) 6: { 7: // note the using here, will call Dispose() when block terminated. 8: using (var seq = new Sequencer(starter)) 9: { 10: // infinite loop on this generator, means must be bounded by caller! 11: while(true) 12: { 13: yield return seq.GetNext(); 14: } 15: } 16: } 17: } This is really the same conundrum as the database problem originally posed. Here we are using iteration (yield return) over a large collection (infinite sequence of integers). If we cut the sequence short by breaking iteration, will that using block exit and hence, Dispose be called? Well, let's see: 1: // The test program class 2: public class IteratorTest 3: { 4: // The main test method. 5: public static void Main() 6: { 7: Console.WriteLine("Going to consume 10 of infinite items"); 8: Console.Out.Flush(); 9:  10: foreach(var i in 0.GetSequence()) 11: { 12: // could use TakeWhile, but wanted to output right at break... 13: if(i >= 10) 14: { 15: Console.WriteLine("Breaking now!"); 16: Console.Out.Flush(); 17: break; 18: } 19:  20: Console.WriteLine(i); 21: Console.Out.Flush(); 22: } 23:  24: Console.WriteLine("Done with loop."); 25: Console.Out.Flush(); 26: } 27: } So, what do we see? Do we see the "Disposed" message from our dispose, or did the Dispose get skipped because from an "eyeball" perspective we should be locked in that infinite generator loop? Here's the results: 1: Going to consume 10 of infinite items 2: 0 3: 1 4: 2 5: 3 6: 4 7: 5 8: 6 9: 7 10: 8 11: 9 12: Breaking now! 13: Disposed with last sequence number of 11! 14: Done with loop. Yes indeed, when we break the loop, the state machine that C# generates for yield iterate exits the iteration through the using blocks and auto-disposes the IDisposable correctly. I must admit, though, the first time I wrote one, I began to wonder and that led to this test. If you've never seen iterators before (I wrote a previous entry here) the infinite loop may throw you, but you have to keep in mind it is not a linear piece of code, that every time you hit a "yield return" it cedes control back to the state machine generated for the iterator. And this state machine, I'm happy to say, is smart enough to clean up the using blocks correctly. I suspected those wily guys and gals at Microsoft engineered it well, and I wasn't disappointed. But, I've been bitten by assumptions before, so it's good to test and see. Yes, maybe you knew it would or figured it would, but isn't it nice to know? And as those campy 80s G.I. Joe cartoon public service reminders always taught us, "Knowing is half the battle...". Technorati Tags: C#,.NET

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  • CodePlex Daily Summary for Sunday, August 03, 2014

    CodePlex Daily Summary for Sunday, August 03, 2014Popular ReleasesBoxStarter: Boxstarter 2.4.76: Running the Setup.bat file will install Chocolatey if not present and then install the Boxstarter modules.GMare: GMare Beta 1.2: Features Added: - Instance painting by holding the alt key down while pressing the left mouse button - Functionality to the binary exporter so that backgrounds from image files can be used - On the binary exporter background information can be edited manually now - Update to the GMare binary read GML script - Game Maker Studio export - Import from GMare project. Multiple options to import desired properties of a .gmpx - 10 undo/redo levels instead of 5 is now the default - New preferences dia...Json.NET: Json.NET 6.0 Release 4: New feature - Added Merge to LINQ to JSON New feature - Added JValue.CreateNull and JValue.CreateUndefined New feature - Added Windows Phone 8.1 support to .NET 4.0 portable assembly New feature - Added OverrideCreator to JsonObjectContract New feature - Added support for overriding the creation of interfaces and abstract types New feature - Added support for reading UUID BSON binary values as a Guid New feature - Added MetadataPropertyHandling.Ignore New feature - Improv...SQL Server Dialog: SQL Server Dialog: Input server, user and password Show folder and file in treeview Customize icon Filter file extension Skip system generate folder and fileAitso-a platform for spatial optimization and based on artificial immune systems: Aitso_0.14.08.01: Aitso0.14.08.01Installer.zipVidCoder: 1.5.24 Beta: Added NL-Means denoiser. Updated HandBrake core to SVN 6254. Added extra error handling to DVD player code to avoid a crash when the player was moved.AutoUpdater.NET : Auto update library for VB.NET and C# Developer: AutoUpdater.NET 1.3: Fixed problem in DownloadUpdateDialog where download continues even if you close the dialog. Added support for new url field for 64 bit application setup. AutoUpdater.NET will decide which download url to use by looking at the value of IntPtr.Size. Added German translation provided by Rene Kannegiesser. Now developer can handle update logic herself using event suggested by ricorx7. Added italian translation provided by Gianluca Mariani. Fixed bug that prevents Application from exiti...SEToolbox: SEToolbox 01.041.012 Release 1: Added voxel material textures to read in with mods. Fixed missing texture replacements for mods. Fixed rounding issue in raytrace code. Fixed repair issue with corrupt checkpoint file. Fixed issue with updated SE binaries 01.041.012 using new container configuration.Magick.NET: Magick.NET 6.8.9.601: Magick.NET linked with ImageMagick 6.8.9.6 Breaking changes: - Changed arguments for the Map method of MagickImage. - QuantizeSettings uses Riemersma by default.Multiple Threads TCP Server: Project: this Project is based on VS 2013, .net freamwork 4.0, you can open it by vs 2010 or laterAricie Shared: Aricie.Shared Version 1.8.00: Version 1.8.0 - Release Notes New: Expression Builder to design Flee Expressions New: Cryptographic helpers and configuration classes Improvement: Many fixes and improvements with property editor Improvement: Token Replace Property explorer now has a restricted mode for additional security Improvement: Better variables, types and object manipulation Fixed: smart file and flee bugs Fixed: Removed Exception while trying to read unsuported files Improvement: several performance twe...Accesorios de sitios Torrent en Español para Synology Download Station: Pack de Torrents en Español 6.0.0: Agregado los módulos de DivXTotal, el módulo de búsqueda depende del de alojamiento para bajar las series Utiliza el rss: http://www.divxtotal.com/rss.php DbEntry.Net (Leafing Framework): DbEntry.Net 4.2: DbEntry.Net is a lightweight Object Relational Mapping (ORM) database access compnent for .Net 4.0+. It has clearly and easily programing interface for ORM and sql directly, and supoorted Access, Sql Server, MySql, SQLite, Firebird, PostgreSQL and Oracle. It also provide a Ruby On Rails style MVC framework. Asp.Net DataSource and a simple IoC. DbEntry.Net.v4.2.Setup.zip include the setup package. DbEntry.Net.v4.2.Src.zip include source files and unit tests. DbEntry.Net.v4.2.Samples.zip ...Azure Storage Explorer: Azure Storage Explorer 6 Preview 1: Welcome to Azure Storage Explorer 6 Preview 1 This is the first release of the latest Azure Storage Explorer, code-named Phoenix. What's New?Here are some important things to know about version 6: Open Source Now being run as a full open source project. Full source code on CodePlex. Collaboration encouraged! Updated Code Base Brand-new code base (WPF/C#/.NET 4.5) Visual Studio 2013 solution (previously VS2010) Uses the Task Parallel Library (TPL) for asynchronous background operat...Wsus Package Publisher: release v1.3.1407.29: Updated WPP to recognize the very latest console version. Some files was missing into the latest release of WPP which lead to crash when trying to make a custom update. Add a workaround to avoid clipboard modification when double-clicking on a label when creating a custom update. Add the ability to publish detectoids. (This feature is still in a BETA phase. Packages relying on these detectoids to determine which computers need to be updated, may apply to all computers).VG-Ripper & PG-Ripper: PG-Ripper 1.4.32: changes NEW: Added Support for 'ImgMega.com' links NEW: Added Support for 'ImgCandy.net' links NEW: Added Support for 'ImgPit.com' links NEW: Added Support for 'Img.yt' links FIXED: 'Radikal.ru' links FIXED: 'ImageTeam.org' links FIXED: 'ImgSee.com' links FIXED: 'Img.yt' linksAsp.Net MVC-4,Entity Framework and JQGrid Demo with Todo List WebApplication: Asp.Net MVC-4,Entity Framework and JQGrid Demo: Asp.Net MVC-4,Entity Framework and JQGrid Demo with simple Todo List WebApplication, Overview TodoList is a simple web application to create, store and modify Todo tasks to be maintained by the users, which comprises of following fields to the user (Task Name, Task Description, Severity, Target Date, Task Status). TodoList web application is created using MVC - 4 architecture, code-first Entity Framework (ORM) and Jqgrid for displaying the data.Waterfox: Waterfox 31.0 Portable: New features in Waterfox 31.0: Added support for Unicode 7.0 Experimental support for WebCL New features in Firefox 31.0:New Add the search field to the new tab page Support of Prefer:Safe http header for parental control mozilla::pkix as default certificate verifier Block malware from downloaded files Block malware from downloaded files audio/video .ogg and .pdf files handled by Firefox if no application specified Changed Removal of the CAPS infrastructure for specifying site-sp...SuperSocket, an extensible socket server framework: SuperSocket 1.6.3: The changes below are included in this release: fixed an exception when collect a server's status but it has been stopped fixed a bug that can cause an exception in case of sending data when the connection dropped already fixed the log4net missing issue for a QuickStart project fixed a warning in a QuickStart projectYnote Classic: Ynote Classic 2.8.5 Beta: Several Changes - Multiple Carets and Multiple Selections - Improved Startup Time - Improved Syntax Highlighting - Search Improvements - Shell Command - Improved StabilityNew ProjectsCreek: Creek is a Collection of many C# Frameworks and my ownSpeaking Speedometer (android): Simple speaking speedometerT125Protocol { Alpha version }: implement T125 Protocol for communicate with a mainframe.Unix Time: This library provides a System.UnixTime as a new Type providing conversion between Unix Time and .NET DateTime.

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  • Why doesn't this code work correctly?

    - by MisterSir
    I'm working on a website that displays galleries, using jCarousel. But no matter what I try, I can't get it to work, and I need to finish this by today. I have a very urgent schedule. My code basically takes image URLs from a database and sends them to AJAX, which passes it to jCarousel which makes the gallery. But there are a few problems: It doesn't display correctly! I can only get the last item pulled from the database, and it displays on the bottom-most row. After the item pulled from the database is displayed, the first time I click on "prev" there's no scroll effect, and the item just disappears! Only if I click on "next" 2-3 times there's a scroll effect and the item remains visible. My items are always displayed at the end of the carousel! This is urgent.. Please help me fix this. about.html: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-us"> <head> <script type="text/javascript" src="jquery-1.4.4.min.js"></script> <script type="text/javascript" src="/lib/jquery.jcarousel.min.js"></script> <link rel="stylesheet" type="text/css" href="/skins/tango/skin.css" /> <!--<style type="text/css"> #wrapper { width: 700px; margin-left: auto; margin-right: auto; } #carousel { margin-top: 120px; padding-left: 120px; } #side { padding-left: 550px; position: absolute; padding-top: 120px; } #hidden { color: #FFFFFF; } </style>--> <script type="text/javascript"> jQuery.easing['BounceEaseOut'] = function(p, t, b, c, d) { if ((t/=d) < (1/2.75)) { return c*(7.5625*t*t) + b; } else if (t < (2/2.75)) { return c*(7.5625*(t-=(1.5/2.75))*t + .75) + b; } else if (t < (2.5/2.75)) { return c*(7.5625*(t-=(2.25/2.75))*t + .9375) + b; } else { return c*(7.5625*(t-=(2.625/2.75))*t + .984375) + b; } }; function mycarousel_initCallback(carousel) { jQuery('#mycarousel-next').bind('click', function() { carousel.next(); return false; }); jQuery('#mycarousel-prev').bind('click', function() { carousel.prev(); return false; }); }; jQuery(document).ready(function() { jQuery('#mycarousel').jcarousel({ easing: 'BounceEaseOut', wrap: "first", initCallback: mycarousel_initCallback, animation: 1000, scroll: 3, visible: 3, buttonNextHTML: null, buttonPrevHTML: null }); jQuery('#mycarousel2').jcarousel({ easing: 'BounceEaseOut', animation: 1000, wrap: "first", initCallback: mycarousel_initCallback, scroll: 3, visible: 3, buttonNextHTML: null, buttonPrevHTML: null }); jQuery('#mycarousel3').jcarousel({ easing: 'BounceEaseOut', animation: 1000, scroll: 3, wrap: "first", initCallback: mycarousel_initCallback, visible: 3, buttonNextHTML: null, buttonPrevHTML: null }); }); var prevButton = null; function getObject(b, el) { var currbutton = b; var http; var url = "about.php"; var parameters = "d=carousel&cat=" + currbutton; try { http = new XMLHttpRequest(); } catch(e) { try { http = new ActiveXObject("Msxml2.XMLHTTP"); } catch(e) { http = new ActiveXObject("Microsoft.XMLHTTP"); } } function getServer() { if (http.readyState == 4) { var i = 0; var liArr = http.responseText; var built = liArr.split(", "); var li = document.createElement("li"); var ul1 = document.getElementById("mycarousel"); var ul2 = document.getElementById("mycarousel2"); var ul3 = document.getElementById("mycarousel3"); if (el != prevButton) { prevButton = el; while (ul1.hasChildNodes() ) {ul1.removeChild(ul1.lastChild);} while (ul2.hasChildNodes() ) {ul2.removeChild(ul2.lastChild);} while (ul3.hasChildNodes() ) {ul3.removeChild(ul3.lastChild);} } else return 0; while (i < (built.length) / 3) { li.innerHTML = built[i]; ul1.appendChild(li); i++; } while (i < ((built.length) / 3)*2) { li.innerHTML = built[i]; ul2.appendChild(li); i++; } while (i < (built.length)) { li.innerHTML = built[i]; ul3.appendChild(li); i++; } } } http.open("POST", url, true); http.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); http.setRequestHeader("Content-length", parameters.length); http.setRequestHeader("Connection", "close"); http.onreadystatechange = getServer; http.send(parameters); } </script> </head> <body> <span id="hidden"> </span> <div id="wrapper"> <div id="side"> <form name="cats"> <input type="button" value="Hats" onclick="getObject('hats', this);"/><br /> <input type="button" value="Pants" onclick="getObject('pants', this);"/><br /> <input type="button" value="Shirts" onclick="getObject('shirts', this);"/><br /> </form> </div> <div id="carousel"> <ul id="mycarousel" class="jcarousel-skin-tango"> </ul> <ul id="mycarousel2" class="jcarousel-skin-tango"> </ul> <ul id="mycarousel3" class="jcarousel-skin-tango"> </ul> <input type="button" id="mycarousel-prev" value="prev" /> <input type="button" id="mycarousel-next" value="next" /> </div> </div> </body> </html> I commented the CSS because I thought it was giving me trouble, but honestly I have no idea what the hell's going on with jCarousel. about.php: <?php echo "<img width='75' height='75' src='http://static.flickr.com/66/199481236_dc98b5abb3_s.jpg' />, hi, hi, hi, hi, hi, hi, hi, hi"; ?> Also, even if there are no other items than what is displayed, I'm still able to scroll back, but not forward, assumingly because my item is always placed at the end of the carousel. I know it looks like a lot of code but it's really not! My formatting takes a lot of lines, the commented CSS takes a lot, and a lot of the code is HTML and jCarousel configuration, and there's also the BounceEasing effect which takes a few lines. There's not much actual code! So as I said, this is urgent and I need this fixed. But I can't get it to work. Please help me! Thanks for your time! EDIT: I changed the code a bit, but it still does not work. I really need help on this one!! EDIT: I added document.createElement("li"); to each while loop. Now all my items are displayed, but they are displayed vertically and not horizontally on each row. Other than that all other problems are the same. EDIT: Oh and also, in the row my image displays, only the image is there. Maybe jCarousel doesn't accept img and text, I don't know.

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  • An Introduction to ASP.NET Web API

    - by Rick Strahl
    Microsoft recently released ASP.NET MVC 4.0 and .NET 4.5 and along with it, the brand spanking new ASP.NET Web API. Web API is an exciting new addition to the ASP.NET stack that provides a new, well-designed HTTP framework for creating REST and AJAX APIs (API is Microsoft’s new jargon for a service, in case you’re wondering). Although Web API ships and installs with ASP.NET MVC 4, you can use Web API functionality in any ASP.NET project, including WebForms, WebPages and MVC or just a Web API by itself. And you can also self-host Web API in your own applications from Console, Desktop or Service applications. If you're interested in a high level overview on what ASP.NET Web API is and how it fits into the ASP.NET stack you can check out my previous post: Where does ASP.NET Web API fit? In the following article, I'll focus on a practical, by example introduction to ASP.NET Web API. All the code discussed in this article is available in GitHub: https://github.com/RickStrahl/AspNetWebApiArticle [republished from my Code Magazine Article and updated for RTM release of ASP.NET Web API] Getting Started To start I’ll create a new empty ASP.NET application to demonstrate that Web API can work with any kind of ASP.NET project. Although you can create a new project based on the ASP.NET MVC/Web API template to quickly get up and running, I’ll take you through the manual setup process, because one common use case is to add Web API functionality to an existing ASP.NET application. This process describes the steps needed to hook up Web API to any ASP.NET 4.0 application. Start by creating an ASP.NET Empty Project. Then create a new folder in the project called Controllers. Add a Web API Controller Class Once you have any kind of ASP.NET project open, you can add a Web API Controller class to it. Web API Controllers are very similar to MVC Controller classes, but they work in any kind of project. Add a new item to this folder by using the Add New Item option in Visual Studio and choose Web API Controller Class, as shown in Figure 1. Figure 1: This is how you create a new Controller Class in Visual Studio   Make sure that the name of the controller class includes Controller at the end of it, which is required in order for Web API routing to find it. Here, the name for the class is AlbumApiController. For this example, I’ll use a Music Album model to demonstrate basic behavior of Web API. The model consists of albums and related songs where an album has properties like Name, Artist and YearReleased and a list of songs with a SongName and SongLength as well as an AlbumId that links it to the album. You can find the code for the model (and the rest of these samples) on Github. To add the file manually, create a new folder called Model, and add a new class Album.cs and copy the code into it. There’s a static AlbumData class with a static CreateSampleAlbumData() method that creates a short list of albums on a static .Current that I’ll use for the examples. Before we look at what goes into the controller class though, let’s hook up routing so we can access this new controller. Hooking up Routing in Global.asax To start, I need to perform the one required configuration task in order for Web API to work: I need to configure routing to the controller. Like MVC, Web API uses routing to provide clean, extension-less URLs to controller methods. Using an extension method to ASP.NET’s static RouteTable class, you can use the MapHttpRoute() (in the System.Web.Http namespace) method to hook-up the routing during Application_Start in global.asax.cs shown in Listing 1.using System; using System.Web.Routing; using System.Web.Http; namespace AspNetWebApi { public class Global : System.Web.HttpApplication { protected void Application_Start(object sender, EventArgs e) { RouteTable.Routes.MapHttpRoute( name: "AlbumVerbs", routeTemplate: "albums/{title}", defaults: new { symbol = RouteParameter.Optional, controller="AlbumApi" } ); } } } This route configures Web API to direct URLs that start with an albums folder to the AlbumApiController class. Routing in ASP.NET is used to create extensionless URLs and allows you to map segments of the URL to specific Route Value parameters. A route parameter, with a name inside curly brackets like {name}, is mapped to parameters on the controller methods. Route parameters can be optional, and there are two special route parameters – controller and action – that determine the controller to call and the method to activate respectively. HTTP Verb Routing Routing in Web API can route requests by HTTP Verb in addition to standard {controller},{action} routing. For the first examples, I use HTTP Verb routing, as shown Listing 1. Notice that the route I’ve defined does not include an {action} route value or action value in the defaults. Rather, Web API can use the HTTP Verb in this route to determine the method to call the controller, and a GET request maps to any method that starts with Get. So methods called Get() or GetAlbums() are matched by a GET request and a POST request maps to a Post() or PostAlbum(). Web API matches a method by name and parameter signature to match a route, query string or POST values. In lieu of the method name, the [HttpGet,HttpPost,HttpPut,HttpDelete, etc] attributes can also be used to designate the accepted verbs explicitly if you don’t want to follow the verb naming conventions. Although HTTP Verb routing is a good practice for REST style resource APIs, it’s not required and you can still use more traditional routes with an explicit {action} route parameter. When {action} is supplied, the HTTP verb routing is ignored. I’ll talk more about alternate routes later. When you’re finished with initial creation of files, your project should look like Figure 2.   Figure 2: The initial project has the new API Controller Album model   Creating a small Album Model Now it’s time to create some controller methods to serve data. For these examples, I’ll use a very simple Album and Songs model to play with, as shown in Listing 2. public class Song { public string AlbumId { get; set; } [Required, StringLength(80)] public string SongName { get; set; } [StringLength(5)] public string SongLength { get; set; } } public class Album { public string Id { get; set; } [Required, StringLength(80)] public string AlbumName { get; set; } [StringLength(80)] public string Artist { get; set; } public int YearReleased { get; set; } public DateTime Entered { get; set; } [StringLength(150)] public string AlbumImageUrl { get; set; } [StringLength(200)] public string AmazonUrl { get; set; } public virtual List<Song> Songs { get; set; } public Album() { Songs = new List<Song>(); Entered = DateTime.Now; // Poor man's unique Id off GUID hash Id = Guid.NewGuid().GetHashCode().ToString("x"); } public void AddSong(string songName, string songLength = null) { this.Songs.Add(new Song() { AlbumId = this.Id, SongName = songName, SongLength = songLength }); } } Once the model has been created, I also added an AlbumData class that generates some static data in memory that is loaded onto a static .Current member. The signature of this class looks like this and that's what I'll access to retrieve the base data:public static class AlbumData { // sample data - static list public static List<Album> Current = CreateSampleAlbumData(); /// <summary> /// Create some sample data /// </summary> /// <returns></returns> public static List<Album> CreateSampleAlbumData() { … }} You can check out the full code for the data generation online. Creating an AlbumApiController Web API shares many concepts of ASP.NET MVC, and the implementation of your API logic is done by implementing a subclass of the System.Web.Http.ApiController class. Each public method in the implemented controller is a potential endpoint for the HTTP API, as long as a matching route can be found to invoke it. The class name you create should end in Controller, which is how Web API matches the controller route value to figure out which class to invoke. Inside the controller you can implement methods that take standard .NET input parameters and return .NET values as results. Web API’s binding tries to match POST data, route values, form values or query string values to your parameters. Because the controller is configured for HTTP Verb based routing (no {action} parameter in the route), any methods that start with Getxxxx() are called by an HTTP GET operation. You can have multiple methods that match each HTTP Verb as long as the parameter signatures are different and can be matched by Web API. In Listing 3, I create an AlbumApiController with two methods to retrieve a list of albums and a single album by its title .public class AlbumApiController : ApiController { public IEnumerable<Album> GetAlbums() { var albums = AlbumData.Current.OrderBy(alb => alb.Artist); return albums; } public Album GetAlbum(string title) { var album = AlbumData.Current .SingleOrDefault(alb => alb.AlbumName.Contains(title)); return album; }} To access the first two requests, you can use the following URLs in your browser: http://localhost/aspnetWebApi/albumshttp://localhost/aspnetWebApi/albums/Dirty%20Deeds Note that you’re not specifying the actions of GetAlbum or GetAlbums in these URLs. Instead Web API’s routing uses HTTP GET verb to route to these methods that start with Getxxx() with the first mapping to the parameterless GetAlbums() method and the latter to the GetAlbum(title) method that receives the title parameter mapped as optional in the route. Content Negotiation When you access any of the URLs above from a browser, you get either an XML or JSON result returned back. The album list result for Chrome 17 and Internet Explorer 9 is shown Figure 3. Figure 3: Web API responses can vary depending on the browser used, demonstrating Content Negotiation in action as these two browsers send different HTTP Accept headers.   Notice that the results are not the same: Chrome returns an XML response and IE9 returns a JSON response. Whoa, what’s going on here? Shouldn’t we see the same result in both browsers? Actually, no. Web API determines what type of content to return based on Accept headers. HTTP clients, like browsers, use Accept headers to specify what kind of content they’d like to see returned. Browsers generally ask for HTML first, followed by a few additional content types. Chrome (and most other major browsers) ask for: Accept: text/html, application/xhtml+xml,application/xml; q=0.9,*/*;q=0.8 IE9 asks for: Accept: text/html, application/xhtml+xml, */* Note that Chrome’s Accept header includes application/xml, which Web API finds in its list of supported media types and returns an XML response. IE9 does not include an Accept header type that works on Web API by default, and so it returns the default format, which is JSON. This is an important and very useful feature that was missing from any previous Microsoft REST tools: Web API automatically switches output formats based on HTTP Accept headers. Nowhere in the server code above do you have to explicitly specify the output format. Rather, Web API determines what format the client is requesting based on the Accept headers and automatically returns the result based on the available formatters. This means that a single method can handle both XML and JSON results.. Using this simple approach makes it very easy to create a single controller method that can return JSON, XML, ATOM or even OData feeds by providing the appropriate Accept header from the client. By default you don’t have to worry about the output format in your code. Note that you can still specify an explicit output format if you choose, either globally by overriding the installed formatters, or individually by returning a lower level HttpResponseMessage instance and setting the formatter explicitly. More on that in a minute. Along the same lines, any content sent to the server via POST/PUT is parsed by Web API based on the HTTP Content-type of the data sent. The same formats allowed for output are also allowed on input. Again, you don’t have to do anything in your code – Web API automatically performs the deserialization from the content. Accessing Web API JSON Data with jQuery A very common scenario for Web API endpoints is to retrieve data for AJAX calls from the Web browser. Because JSON is the default format for Web API, it’s easy to access data from the server using jQuery and its getJSON() method. This example receives the albums array from GetAlbums() and databinds it into the page using knockout.js.$.getJSON("albums/", function (albums) { // make knockout template visible $(".album").show(); // create view object and attach array var view = { albums: albums }; ko.applyBindings(view); }); Figure 4 shows this and the next example’s HTML output. You can check out the complete HTML and script code at http://goo.gl/Ix33C (.html) and http://goo.gl/tETlg (.js). Figu Figure 4: The Album Display sample uses JSON data loaded from Web API.   The result from the getJSON() call is a JavaScript object of the server result, which comes back as a JavaScript array. In the code, I use knockout.js to bind this array into the UI, which as you can see, requires very little code, instead using knockout’s data-bind attributes to bind server data to the UI. Of course, this is just one way to use the data – it’s entirely up to you to decide what to do with the data in your client code. Along the same lines, I can retrieve a single album to display when the user clicks on an album. The response returns the album information and a child array with all the songs. The code to do this is very similar to the last example where we pulled the albums array:$(".albumlink").live("click", function () { var id = $(this).data("id"); // title $.getJSON("albums/" + id, function (album) { ko.applyBindings(album, $("#divAlbumDialog")[0]); $("#divAlbumDialog").show(); }); }); Here the URL looks like this: /albums/Dirty%20Deeds, where the title is the ID captured from the clicked element’s data ID attribute. Explicitly Overriding Output Format When Web API automatically converts output using content negotiation, it does so by matching Accept header media types to the GlobalConfiguration.Configuration.Formatters and the SupportedMediaTypes of each individual formatter. You can add and remove formatters to globally affect what formats are available and it’s easy to create and plug in custom formatters.The example project includes a JSONP formatter that can be plugged in to provide JSONP support for requests that have a callback= querystring parameter. Adding, removing or replacing formatters is a global option you can use to manipulate content. It’s beyond the scope of this introduction to show how it works, but you can review the sample code or check out my blog entry on the subject (http://goo.gl/UAzaR). If automatic processing is not desirable in a particular Controller method, you can override the response output explicitly by returning an HttpResponseMessage instance. HttpResponseMessage is similar to ActionResult in ASP.NET MVC in that it’s a common way to return an abstract result message that contains content. HttpResponseMessage s parsed by the Web API framework using standard interfaces to retrieve the response data, status code, headers and so on[MS2] . Web API turns every response – including those Controller methods that return static results – into HttpResponseMessage instances. Explicitly returning an HttpResponseMessage instance gives you full control over the output and lets you mostly bypass WebAPI’s post-processing of the HTTP response on your behalf. HttpResponseMessage allows you to customize the response in great detail. Web API’s attention to detail in the HTTP spec really shows; many HTTP options are exposed as properties and enumerations with detailed IntelliSense comments. Even if you’re new to building REST-based interfaces, the API guides you in the right direction for returning valid responses and response codes. For example, assume that I always want to return JSON from the GetAlbums() controller method and ignore the default media type content negotiation. To do this, I can adjust the output format and headers as shown in Listing 4.public HttpResponseMessage GetAlbums() { var albums = AlbumData.Current.OrderBy(alb => alb.Artist); // Create a new HttpResponse with Json Formatter explicitly var resp = new HttpResponseMessage(HttpStatusCode.OK); resp.Content = new ObjectContent<IEnumerable<Album>>( albums, new JsonMediaTypeFormatter()); // Get Default Formatter based on Content Negotiation //var resp = Request.CreateResponse<IEnumerable<Album>>(HttpStatusCode.OK, albums); resp.Headers.ConnectionClose = true; resp.Headers.CacheControl = new CacheControlHeaderValue(); resp.Headers.CacheControl.Public = true; return resp; } This example returns the same IEnumerable<Album> value, but it wraps the response into an HttpResponseMessage so you can control the entire HTTP message result including the headers, formatter and status code. In Listing 4, I explicitly specify the formatter using the JsonMediaTypeFormatter to always force the content to JSON.  If you prefer to use the default content negotiation with HttpResponseMessage results, you can create the Response instance using the Request.CreateResponse method:var resp = Request.CreateResponse<IEnumerable<Album>>(HttpStatusCode.OK, albums); This provides you an HttpResponse object that's pre-configured with the default formatter based on Content Negotiation. Once you have an HttpResponse object you can easily control most HTTP aspects on this object. What's sweet here is that there are many more detailed properties on HttpResponse than the core ASP.NET Response object, with most options being explicitly configurable with enumerations that make it easy to pick the right headers and response codes from a list of valid codes. It makes HTTP features available much more discoverable even for non-hardcore REST/HTTP geeks. Non-Serialized Results The output returned doesn’t have to be a serialized value but can also be raw data, like strings, binary data or streams. You can use the HttpResponseMessage.Content object to set a number of common Content classes. Listing 5 shows how to return a binary image using the ByteArrayContent class from a Controller method. [HttpGet] public HttpResponseMessage AlbumArt(string title) { var album = AlbumData.Current.FirstOrDefault(abl => abl.AlbumName.StartsWith(title)); if (album == null) { var resp = Request.CreateResponse<ApiMessageError>( HttpStatusCode.NotFound, new ApiMessageError("Album not found")); return resp; } // kinda silly - we would normally serve this directly // but hey - it's a demo. var http = new WebClient(); var imageData = http.DownloadData(album.AlbumImageUrl); // create response and return var result = new HttpResponseMessage(HttpStatusCode.OK); result.Content = new ByteArrayContent(imageData); result.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg"); return result; } The image retrieval from Amazon is contrived, but it shows how to return binary data using ByteArrayContent. It also demonstrates that you can easily return multiple types of content from a single controller method, which is actually quite common. If an error occurs - such as a resource can’t be found or a validation error – you can return an error response to the client that’s very specific to the error. In GetAlbumArt(), if the album can’t be found, we want to return a 404 Not Found status (and realistically no error, as it’s an image). Note that if you are not using HTTP Verb-based routing or not accessing a method that starts with Get/Post etc., you have to specify one or more HTTP Verb attributes on the method explicitly. Here, I used the [HttpGet] attribute to serve the image. Another option to handle the error could be to return a fixed placeholder image if no album could be matched or the album doesn’t have an image. When returning an error code, you can also return a strongly typed response to the client. For example, you can set the 404 status code and also return a custom error object (ApiMessageError is a class I defined) like this:return Request.CreateResponse<ApiMessageError>( HttpStatusCode.NotFound, new ApiMessageError("Album not found") );   If the album can be found, the image will be returned. The image is downloaded into a byte[] array, and then assigned to the result’s Content property. I created a new ByteArrayContent instance and assigned the image’s bytes and the content type so that it displays properly in the browser. There are other content classes available: StringContent, StreamContent, ByteArrayContent, MultipartContent, and ObjectContent are at your disposal to return just about any kind of content. You can create your own Content classes if you frequently return custom types and handle the default formatter assignments that should be used to send the data out . Although HttpResponseMessage results require more code than returning a plain .NET value from a method, it allows much more control over the actual HTTP processing than automatic processing. It also makes it much easier to test your controller methods as you get a response object that you can check for specific status codes and output messages rather than just a result value. Routing Again Ok, let’s get back to the image example. Using the original routing we have setup using HTTP Verb routing there's no good way to serve the image. In order to return my album art image I’d like to use a URL like this: http://localhost/aspnetWebApi/albums/Dirty%20Deeds/image In order to create a URL like this, I have to create a new Controller because my earlier routes pointed to the AlbumApiController using HTTP Verb routing. HTTP Verb based routing is great for representing a single set of resources such as albums. You can map operations like add, delete, update and read easily using HTTP Verbs. But you cannot mix action based routing into a an HTTP Verb routing controller - you can only map HTTP Verbs and each method has to be unique based on parameter signature. You can't have multiple GET operations to methods with the same signature. So GetImage(string id) and GetAlbum(string title) are in conflict in an HTTP GET routing scenario. In fact, I was unable to make the above Image URL work with any combination of HTTP Verb plus Custom routing using the single Albums controller. There are number of ways around this, but all involve additional controllers.  Personally, I think it’s easier to use explicit Action routing and then add custom routes if you need to simplify your URLs further. So in order to accommodate some of the other examples, I created another controller – AlbumRpcApiController – to handle all requests that are explicitly routed via actions (/albums/rpc/AlbumArt) or are custom routed with explicit routes defined in the HttpConfiguration. I added the AlbumArt() method to this new AlbumRpcApiController class. For the image URL to work with the new AlbumRpcApiController, you need a custom route placed before the default route from Listing 1.RouteTable.Routes.MapHttpRoute( name: "AlbumRpcApiAction", routeTemplate: "albums/rpc/{action}/{title}", defaults: new { title = RouteParameter.Optional, controller = "AlbumRpcApi", action = "GetAblums" } ); Now I can use either of the following URLs to access the image: Custom route: (/albums/rpc/{title}/image)http://localhost/aspnetWebApi/albums/PowerAge/image Action route: (/albums/rpc/action/{title})http://localhost/aspnetWebAPI/albums/rpc/albumart/PowerAge Sending Data to the Server To send data to the server and add a new album, you can use an HTTP POST operation. Since I’m using HTTP Verb-based routing in the original AlbumApiController, I can implement a method called PostAlbum()to accept a new album from the client. Listing 6 shows the Web API code to add a new album.public HttpResponseMessage PostAlbum(Album album) { if (!this.ModelState.IsValid) { // my custom error class var error = new ApiMessageError() { message = "Model is invalid" }; // add errors into our client error model for client foreach (var prop in ModelState.Values) { var modelError = prop.Errors.FirstOrDefault(); if (!string.IsNullOrEmpty(modelError.ErrorMessage)) error.errors.Add(modelError.ErrorMessage); else error.errors.Add(modelError.Exception.Message); } return Request.CreateResponse<ApiMessageError>(HttpStatusCode.Conflict, error); } // update song id which isn't provided foreach (var song in album.Songs) song.AlbumId = album.Id; // see if album exists already var matchedAlbum = AlbumData.Current .SingleOrDefault(alb => alb.Id == album.Id || alb.AlbumName == album.AlbumName); if (matchedAlbum == null) AlbumData.Current.Add(album); else matchedAlbum = album; // return a string to show that the value got here var resp = Request.CreateResponse(HttpStatusCode.OK, string.Empty); resp.Content = new StringContent(album.AlbumName + " " + album.Entered.ToString(), Encoding.UTF8, "text/plain"); return resp; } The PostAlbum() method receives an album parameter, which is automatically deserialized from the POST buffer the client sent. The data passed from the client can be either XML or JSON. Web API automatically figures out what format it needs to deserialize based on the content type and binds the content to the album object. Web API uses model binding to bind the request content to the parameter(s) of controller methods. Like MVC you can check the model by looking at ModelState.IsValid. If it’s not valid, you can run through the ModelState.Values collection and check each binding for errors. Here I collect the error messages into a string array that gets passed back to the client via the result ApiErrorMessage object. When a binding error occurs, you’ll want to return an HTTP error response and it’s best to do that with an HttpResponseMessage result. In Listing 6, I used a custom error class that holds a message and an array of detailed error messages for each binding error. I used this object as the content to return to the client along with my Conflict HTTP Status Code response. If binding succeeds, the example returns a string with the name and date entered to demonstrate that you captured the data. Normally, a method like this should return a Boolean or no response at all (HttpStatusCode.NoConent). The sample uses a simple static list to hold albums, so once you’ve added the album using the Post operation, you can hit the /albums/ URL to see that the new album was added. The client jQuery code to call the POST operation from the client with jQuery is shown in Listing 7. var id = new Date().getTime().toString(); var album = { "Id": id, "AlbumName": "Power Age", "Artist": "AC/DC", "YearReleased": 1977, "Entered": "2002-03-11T18:24:43.5580794-10:00", "AlbumImageUrl": http://ecx.images-amazon.com/images/…, "AmazonUrl": http://www.amazon.com/…, "Songs": [ { "SongName": "Rock 'n Roll Damnation", "SongLength": 3.12}, { "SongName": "Downpayment Blues", "SongLength": 4.22 }, { "SongName": "Riff Raff", "SongLength": 2.42 } ] } $.ajax( { url: "albums/", type: "POST", contentType: "application/json", data: JSON.stringify(album), processData: false, beforeSend: function (xhr) { // not required since JSON is default output xhr.setRequestHeader("Accept", "application/json"); }, success: function (result) { // reload list of albums page.loadAlbums(); }, error: function (xhr, status, p3, p4) { var err = "Error"; if (xhr.responseText && xhr.responseText[0] == "{") err = JSON.parse(xhr.responseText).message; alert(err); } }); The code in Listing 7 creates an album object in JavaScript to match the structure of the .NET Album class. This object is passed to the $.ajax() function to send to the server as POST. The data is turned into JSON and the content type set to application/json so that the server knows what to convert when deserializing in the Album instance. The jQuery code hooks up success and failure events. Success returns the result data, which is a string that’s echoed back with an alert box. If an error occurs, jQuery returns the XHR instance and status code. You can check the XHR to see if a JSON object is embedded and if it is, you can extract it by de-serializing it and accessing the .message property. REST standards suggest that updates to existing resources should use PUT operations. REST standards aside, I’m not a big fan of separating out inserts and updates so I tend to have a single method that handles both. But if you want to follow REST suggestions, you can create a PUT method that handles updates by forwarding the PUT operation to the POST method:public HttpResponseMessage PutAlbum(Album album) { return PostAlbum(album); } To make the corresponding $.ajax() call, all you have to change from Listing 7 is the type: from POST to PUT. Model Binding with UrlEncoded POST Variables In the example in Listing 7 I used JSON objects to post a serialized object to a server method that accepted an strongly typed object with the same structure, which is a common way to send data to the server. However, Web API supports a number of different ways that data can be received by server methods. For example, another common way is to use plain UrlEncoded POST  values to send to the server. Web API supports Model Binding that works similar (but not the same) as MVC's model binding where POST variables are mapped to properties of object parameters of the target method. This is actually quite common for AJAX calls that want to avoid serialization and the potential requirement of a JSON parser on older browsers. For example, using jQUery you might use the $.post() method to send a new album to the server (albeit one without songs) using code like the following:$.post("albums/",{AlbumName: "Dirty Deeds", YearReleased: 1976 … },albumPostCallback); Although the code looks very similar to the client code we used before passing JSON, here the data passed is URL encoded values (AlbumName=Dirty+Deeds&YearReleased=1976 etc.). Web API then takes this POST data and maps each of the POST values to the properties of the Album object in the method's parameter. Although the client code is different the server can both handle the JSON object, or the UrlEncoded POST values. Dynamic Access to POST Data There are also a few options available to dynamically access POST data, if you know what type of data you're dealing with. If you have POST UrlEncoded values, you can dynamically using a FormsDataCollection:[HttpPost] public string PostAlbum(FormDataCollection form) { return string.Format("{0} - released {1}", form.Get("AlbumName"),form.Get("RearReleased")); } The FormDataCollection is a very simple object, that essentially provides the same functionality as Request.Form[] in ASP.NET. Request.Form[] still works if you're running hosted in an ASP.NET application. However as a general rule, while ASP.NET's functionality is always available when running Web API hosted inside of an  ASP.NET application, using the built in classes specific to Web API makes it possible to run Web API applications in a self hosted environment outside of ASP.NET. If your client is sending JSON to your server, and you don't want to map the JSON to a strongly typed object because you only want to retrieve a few simple values, you can also accept a JObject parameter in your API methods:[HttpPost] public string PostAlbum(JObject jsonData) { dynamic json = jsonData; JObject jalbum = json.Album; JObject juser = json.User; string token = json.UserToken; var album = jalbum.ToObject<Album>(); var user = juser.ToObject<User>(); return String.Format("{0} {1} {2}", album.AlbumName, user.Name, token); } There quite a few options available to you to receive data with Web API, which gives you more choices for the right tool for the job. Unfortunately one shortcoming of Web API is that POST data is always mapped to a single parameter. This means you can't pass multiple POST parameters to methods that receive POST data. It's possible to accept multiple parameters, but only one can map to the POST content - the others have to come from the query string or route values. I have a couple of Blog POSTs that explain what works and what doesn't here: Passing multiple POST parameters to Web API Controller Methods Mapping UrlEncoded POST Values in ASP.NET Web API   Handling Delete Operations Finally, to round out the server API code of the album example we've been discussin, here’s the DELETE verb controller method that allows removal of an album by its title:public HttpResponseMessage DeleteAlbum(string title) { var matchedAlbum = AlbumData.Current.Where(alb => alb.AlbumName == title) .SingleOrDefault(); if (matchedAlbum == null) return new HttpResponseMessage(HttpStatusCode.NotFound); AlbumData.Current.Remove(matchedAlbum); return new HttpResponseMessage(HttpStatusCode.NoContent); } To call this action method using jQuery, you can use:$(".removeimage").live("click", function () { var $el = $(this).parent(".album"); var txt = $el.find("a").text(); $.ajax({ url: "albums/" + encodeURIComponent(txt), type: "Delete", success: function (result) { $el.fadeOut().remove(); }, error: jqError }); }   Note the use of the DELETE verb in the $.ajax() call, which routes to DeleteAlbum on the server. DELETE is a non-content operation, so you supply a resource ID (the title) via route value or the querystring. Routing Conflicts In all requests with the exception of the AlbumArt image example shown so far, I used HTTP Verb routing that I set up in Listing 1. HTTP Verb Routing is a recommendation that is in line with typical REST access to HTTP resources. However, it takes quite a bit of effort to create REST-compliant API implementations based only on HTTP Verb routing only. You saw one example that didn’t really fit – the return of an image where I created a custom route albums/{title}/image that required creation of a second controller and a custom route to work. HTTP Verb routing to a controller does not mix with custom or action routing to the same controller because of the limited mapping of HTTP verbs imposed by HTTP Verb routing. To understand some of the problems with verb routing, let’s look at another example. Let’s say you create a GetSortableAlbums() method like this and add it to the original AlbumApiController accessed via HTTP Verb routing:[HttpGet] public IQueryable<Album> SortableAlbums() { var albums = AlbumData.Current; // generally should be done only on actual queryable results (EF etc.) // Done here because we're running with a static list but otherwise might be slow return albums.AsQueryable(); } If you compile this code and try to now access the /albums/ link, you get an error: Multiple Actions were found that match the request. HTTP Verb routing only allows access to one GET operation per parameter/route value match. If more than one method exists with the same parameter signature, it doesn’t work. As I mentioned earlier for the image display, the only solution to get this method to work is to throw it into another controller. Because I already set up the AlbumRpcApiController I can add the method there. First, I should rename the method to SortableAlbums() so I’m not using a Get prefix for the method. This also makes the action parameter look cleaner in the URL - it looks less like a method and more like a noun. I can then create a new route that handles direct-action mapping:RouteTable.Routes.MapHttpRoute( name: "AlbumRpcApiAction", routeTemplate: "albums/rpc/{action}/{title}", defaults: new { title = RouteParameter.Optional, controller = "AlbumRpcApi", action = "GetAblums" } ); As I am explicitly adding a route segment – rpc – into the route template, I can now reference explicit methods in the Web API controller using URLs like this: http://localhost/AspNetWebApi/rpc/SortableAlbums Error Handling I’ve already done some minimal error handling in the examples. For example in Listing 6, I detected some known-error scenarios like model validation failing or a resource not being found and returning an appropriate HttpResponseMessage result. But what happens if your code just blows up or causes an exception? If you have a controller method, like this:[HttpGet] public void ThrowException() { throw new UnauthorizedAccessException("Unauthorized Access Sucka"); } You can call it with this: http://localhost/AspNetWebApi/albums/rpc/ThrowException The default exception handling displays a 500-status response with the serialized exception on the local computer only. When you connect from a remote computer, Web API throws back a 500  HTTP Error with no data returned (IIS then adds its HTML error page). The behavior is configurable in the GlobalConfiguration:GlobalConfiguration .Configuration .IncludeErrorDetailPolicy = IncludeErrorDetailPolicy.Never; If you want more control over your error responses sent from code, you can throw explicit error responses yourself using HttpResponseException. When you throw an HttpResponseException the response parameter is used to generate the output for the Controller action. [HttpGet] public void ThrowError() { var resp = Request.CreateResponse<ApiMessageError>( HttpStatusCode.BadRequest, new ApiMessageError("Your code stinks!")); throw new HttpResponseException(resp); } Throwing an HttpResponseException stops the processing of the controller method and immediately returns the response you passed to the exception. Unlike other Exceptions fired inside of WebAPI, HttpResponseException bypasses the Exception Filters installed and instead just outputs the response you provide. In this case, the serialized ApiMessageError result string is returned in the default serialization format – XML or JSON. You can pass any content to HttpResponseMessage, which includes creating your own exception objects and consistently returning error messages to the client. Here’s a small helper method on the controller that you might use to send exception info back to the client consistently:private void ThrowSafeException(string message, HttpStatusCode statusCode = HttpStatusCode.BadRequest) { var errResponse = Request.CreateResponse<ApiMessageError>(statusCode, new ApiMessageError() { message = message }); throw new HttpResponseException(errResponse); } You can then use it to output any captured errors from code:[HttpGet] public void ThrowErrorSafe() { try { List<string> list = null; list.Add("Rick"); } catch (Exception ex) { ThrowSafeException(ex.Message); } }   Exception Filters Another more global solution is to create an Exception Filter. Filters in Web API provide the ability to pre- and post-process controller method operations. An exception filter looks at all exceptions fired and then optionally creates an HttpResponseMessage result. Listing 8 shows an example of a basic Exception filter implementation.public class UnhandledExceptionFilter : ExceptionFilterAttribute { public override void OnException(HttpActionExecutedContext context) { HttpStatusCode status = HttpStatusCode.InternalServerError; var exType = context.Exception.GetType(); if (exType == typeof(UnauthorizedAccessException)) status = HttpStatusCode.Unauthorized; else if (exType == typeof(ArgumentException)) status = HttpStatusCode.NotFound; var apiError = new ApiMessageError() { message = context.Exception.Message }; // create a new response and attach our ApiError object // which now gets returned on ANY exception result var errorResponse = context.Request.CreateResponse<ApiMessageError>(status, apiError); context.Response = errorResponse; base.OnException(context); } } Exception Filter Attributes can be assigned to an ApiController class like this:[UnhandledExceptionFilter] public class AlbumRpcApiController : ApiController or you can globally assign it to all controllers by adding it to the HTTP Configuration's Filters collection:GlobalConfiguration.Configuration.Filters.Add(new UnhandledExceptionFilter()); The latter is a great way to get global error trapping so that all errors (short of hard IIS errors and explicit HttpResponseException errors) return a valid error response that includes error information in the form of a known-error object. Using a filter like this allows you to throw an exception as you normally would and have your filter create a response in the appropriate output format that the client expects. For example, an AJAX application can on failure expect to see a JSON error result that corresponds to the real error that occurred rather than a 500 error along with HTML error page that IIS throws up. You can even create some custom exceptions so you can differentiate your own exceptions from unhandled system exceptions - you often don't want to display error information from 'unknown' exceptions as they may contain sensitive system information or info that's not generally useful to users of your application/site. This is just one example of how ASP.NET Web API is configurable and extensible. Exception filters are just one example of how you can plug-in into the Web API request flow to modify output. Many more hooks exist and I’ll take a closer look at extensibility in Part 2 of this article in the future. Summary Web API is a big improvement over previous Microsoft REST and AJAX toolkits. The key features to its usefulness are its ease of use with simple controller based logic, familiar MVC-style routing, low configuration impact, extensibility at all levels and tight attention to exposing and making HTTP semantics easily discoverable and easy to use. Although none of the concepts used in Web API are new or radical, Web API combines the best of previous platforms into a single framework that’s highly functional, easy to work with, and extensible to boot. I think that Microsoft has hit a home run with Web API. Related Resources Where does ASP.NET Web API fit? Sample Source Code on GitHub Passing multiple POST parameters to Web API Controller Methods Mapping UrlEncoded POST Values in ASP.NET Web API Creating a JSONP Formatter for ASP.NET Web API Removing the XML Formatter from ASP.NET Web API Applications© Rick Strahl, West Wind Technologies, 2005-2012Posted in Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • Installing google chrome on RHEL 5.3

    - by Xinus
    I am trying to install Google chrome on RHEL 5.3 but getting error as Missing Dependency: libnss3.so(NSS_3.12.3) is needed by package google-chrome-beta-4.0.249.43-34537.i386 (/root/Desktop/google-chrome-beta_current_i386.rpm) Missing Dependency: xdg-utils is needed by package google-chrome-beta-4.0.249.43-34537.i386 (/root/Desktop/google-chrome-beta_current_i386.rpm) Missing Dependency: lsb >= 3.2 is needed by package google-chrome-beta-4.0.249.43-34537.i386 (/root/Desktop/google-chrome-beta_current_i386.rpm) When try to install lsb package , I get output as [root@localhost softwares]# yum install redhat-lsb Loaded plugins: rhnplugin, security This system is not registered with RHN. RHN support will be disabled. Setting up Install Process Parsing package install arguments Package redhat-lsb-3.1-12.3.EL.i386 installed and not available Nothing to do

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