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  • Tigther code - javascript object array

    - by Scott Silvi
    Inside the callback of a $.getJSON call, I have the code outlined below. The first for block aggregates 'total' & assigns values to sov[i]. The map function calculates the percentage of total. I then instantiate a variable called sovData. With the jQuery Flot graph, any objects that are empty aren't added to the pie chart, so this works for up to 7 different slices/datasets. What I'd like to do is only initialize the ones I need (e.g. sovData would have up to 'howMany - 1' (kws.length -1 ) objects inside of it, likely via something similar to dashboards[i] & sov[i]. How would I do this? Code: var sov = [], howMany = kws.length, total = 0, i = 0; for ( i; i < howMany; i++) { total += sov[ i ] = +parseInt(data.sov['sov' + ( i+1 ) ],10) || 0; } var dashboards = data.dashboards; sov = $.map( sov, function(v) { var s = Math.round( ( (v / total) * 10e3 ) / 100); return s < 1 ? 1 : s; }); var sovData = [{ label : dashboards[0], data : sov[0] }, { label : dashboards[1], data : sov[1] }, { label : dashboards[2], data : sov[2] }, { label : dashboards[3], data : sov[3] }, { label : dashboards[4], data : sov[4] }, { label : dashboards[5], data : sov[5] }, { label : dashboards[6], data : sov[6] } ]

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  • How to understand if (name in {}) in javascript?

    - by tiplip
    I encounter a js function snippet, list as follows each = function(obj, fun) { if (typeof fun != "function") { return obj } if (obj) { var return_value; if (obj.length === undefined) { for (var name in obj) { if (name in {}) { // how to undertand this line, what's purpose? continue } return_value = fun.call(obj[name], obj[name], name); if (return_value == "break") { break } } } else { for (var i = 0, length = obj.length; i < length; i++) { return_value = fun.call(obj[i], obj[i], i); if (return_value == "break") { break } } } } return obj }; Thanks for your answer:)

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  • Howto create own Jquery Like Function in Javascript?

    - by streetparade
    How can i create a function which looks like the jquery callback $ Say i want to call a element with id= "mydiv". i want to be able to call it like var div = $("mydiv").value; i think the function should look like function $(element) { return document.getElementById(element); } Is that the right way to do it, or do you prefer another way to solve it?

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  • Async run for javascript by using listeners

    - by CharlieShi
    I have two functions, the names are Function3, Function4, Function3 will send request to server side to get jsondata by using ajax, which, however, will take about 3 seconds to complete. Function4 is a common function which will wait for Function3's result and then action. My code puts below: function ajaxRequest(container) { $.ajax({ url: "Home/GetResult", type: "post", success: function (data) { container.append(data.message); } }); } var eventable = { on: function (event, cb) { $(this).on(event, cb); }, trigger: function (event) { $(this).trigger(event); } } var Function3 = { run: function () { var self = this; setTimeout(function () { ajaxRequest($(".container1")); self.trigger('done'); }, 500); } } var Function4 = { run: function () { var self = this; setTimeout(function () { $(".container1").append("Function4 complete"); self.trigger('done'); },500); } } $.extend(Function3, eventable); $.extend(Function4, eventable); Function3.on('done', function (event) { Function4.run(); }); Function4.on('done', function () { $(".container1").append("All done"); }); Function3.run(); but now the problem is, when I start the code , it always show me the result as : first will appear "Function4 complete", then "All done" follows, 3 seconds later, "Function3 complete" will appear. That's out of my expection because my expection is "Function3 complete" comes first, "Function4 complete" comes second and "All done" is expected as the last one. Anyone can help me on this? thx in advice. EDIT: I have included all the functions above now. Also, you can check the js script in JSFIDDER: http://jsfiddle.net/sporto/FYBjc/light/ I have replaced the function in JSFIDDER from a common array push action to ajax request.

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  • make selectable area using javascript

    - by Mher
    lets say I have a html page. <html> <body> ... This is my HTML Page, full of html objects and mouse events on them ... <div id='blocker' style="height: 100%; position: absolute; width: 100%; top: 0px; left: 0px; right: 0px; bottom: 0px; z-index: 1001; background: none repeat scroll 0% 0% black; opacity: 0.5;"></div> <div id='window_to_my_html_page' style="display: block; left: 50px; top: 50px; width: 200px; height: 200px; z-index: 1002; position: absolute;"></div> </body> </html> In this example div which id is 'blocker' will block all mouse events from my page. All my HTML page elements behind of my second div(which id is 'window_to_my_html_page') must be active, all mouse events must work on them, this div must be like a window to my HTML page I want to make all elements from my HTML page active(to work as normal) inside this area (left: 50px; top: 50px; width: 200px; height: 200px).... and other content, outside of this area make inactive The question: how can I do it?

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  • [JavaScript] Function making a slight miscalculation.

    - by Stanni
    Hi, To begin with, I have a database that holds map data for a game I am creating. A script on my page uses JSON to retrieve a certain amount of that data from the database and store it in an array. When the data is retrieved it goes through a function that finds out how many individual tiles are used in that particular area. Here is the code: var xmlhttp = new XMLHttpRequest; xmlhttp.onreadystatechange = function(){ if(xmlhttp.readyState == 4){ var map = JSON.parse(xmlhttp.responseText); var mapTiles = new Array; for(var count = 0; count < map.length; count ++){ if(map[count]){ if(map[count]['tile'] in mapTiles == false){ mapTiles.push(map[count]['tile']); } } } alert(mapTiles); } } For each time the script finds a tile number that isn't already in the mapTiles array it adds it to it. Currently, the script is fetching 1024 records that all but one contain the tile value of '1' the other of which contains the tile value of '2'. This means that when I alert the mapTiles array it should display "1, 2" but instead it displays "1, 1, 2". So there is a slight error in the script but I cannot find it.

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  • javascript form reset function not working

    - by daniel
    <form name="mysqlDetails"> <label class="text">url:</label><input id="url" type="text" name="url"/><br/> <label class="text">country:</label><input id="country" type="text" name="country"/><br/> ... <input type="button" id="button" value="save" onclick="ajax.insert('mysqlDetails')"/> <input type="reset" id="clear" value="clear"/> <input type="checkbox" id="autoclear"/><label>autoclear</label> </form> function autoclear(frm){ if(document.forms[frm].getElementById('autoclear').checked==true){ document.forms[frm].reset(); document.forms[frm].getElementById('autoclear').checked=true; } } this.connect=function(frm){ if (isFirefox() && firefoxVersion() >= 3) { httpReq.onload = check; } else { httpReq.onreadystatechange = check; } httpReq.open('GET',url(frm),false); httpReq.send(null); autoclear(frm); } js is located in external file. executing form reset with an non-external file function works fine. why?

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  • Javascript trouble changing opacity

    - by Ghilliedrone
    I'm making script that fades 3 pictures out in order, but the pictures' opacity aren't changing. The if statements are reached but the pictures do not change. The first picture changes to 1 opacity on the page load, so I don't see why it wouldn't work in my function. window.onload = function() { document.getElementById("img1").style.opacity = 1; setInterval(swapPictures, 2000); }; var swapPictures = function(){ if(typeof swapPictures.img1v === 'undefined'){ swapPictures.img1v = true; } if(typeof swapPictures.img2v === 'undefined'){ swapPictures.img2v = false; } if(typeof swapPictures.img3v === 'undefined'){ swapPictures.img3v = false; } if(swapPictures.img1v && !swapPictures.img2v && !swapPictures.img3v){ swapPictures.img1v = !swapPictures.img1v; swapPictures.img2v = !swapPictures.img2v; document.getElementById("img1").style.opacity = .4; document.getElementById("imgtwo").style.opactiy = 1; }else if(!swapPictures.img1v && swapPictures.img2v && !swapPictures.img3v){ swapPictures.img2v = !swapPictures.img2v; swapPictures.img3v = !swapPictures.img3v; document.getElementById("imgtwo").style.opacity = .4; document.getElementById("imgthree").style.opactiy = 1; }else if(!swapPictures.img1v && !swapPictures.img2v && swapPictures.img3v){ swapPictures.img3v = !swapPictures.img3v; swapPictures.img1v = !swapPictures.img1v; document.getElementById("imgthree").style.opacity = .4; document.getElementById("img1").style.opactiy = 1; } };

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  • Javascript A thank you page with user name on it

    - by Sarahfromnowhere
    I have a form where a user input name and other contact information. I validate the input and then redirect to a thank you page. I wanted to personalize the page by having the user name appear as part of the thank you note. I tried document.getElementById(Name1).value to retrieve the value of the Name but it it is giving Undefined. Is there a way for me to set the value of the Name1 field to another variable that I call again to include it in my text message?

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  • Javascript handle 2 data attribute

    - by user3530661
    I need to use data attribute in my html like <div id="userlist" data-user="A.A.M"></div> then I need to alert the data-user I used var userlist = document.getElementById("userlist"); var show = userlist.getAttribute("data-user"); alert(show); My question is how to handle many data-user in the html like <div id="userlist" data-user="A.A.M"></div> <div id="userlist2" data-user="A.A.M2"></div> to alert A.A.M and A.A.M2 Thanks in advance and sorry for my bad English.

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  • Improperly called Javascript function (parameter issue)

    - by 13rave
    I am trying to echo some HTML using PHP in a div. Everything was working until I tried to pass a parameter to the onclick=\"loadpuzzle()\" function. It ran fine when I tried onclick=\"loadpuzzle(4)\" and the function took the parameter and executed normally, but what I need is to pass the value from $row['puzzlename'] as the parameter, which I assume is a string (and so I enclosed it in quotation marks). echo "<td><input id=\"".$row['puzzlename']."\" type=\"radio\" name=\"puzzle-set\" class=\"puzzle_selector\" onclick=\"loadpuzzle(\"".$row['puzzlename']."\")\"/> <label for=\"".$row['puzzlename']."\" class=\"puzz_label\">".$row['puzzlename']."</label></td>"; I am getting a weird error in Safari when I try to run this. "Unexpected token: '}' ". Does anyone know what I am doing wrong here? Why won't it take this parameter? Thank you!

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  • options[Text] is null or not an object in javascript

    - by user9167
    I am getting options[text] is null or not an object error. What i am trying to do here is i am checking what all multi select lookup column values are selected , comparing them with the value in an array and then removing them var responsibleselected = returntags("select","Responsibility selected values"); for(var i=0;i<responsibleselected.options.length;i++) { if(responsibleselected.options[i].selected == true) { for(var j=0;j< ResponsibleArray.length;j++) { if(responsibleselected.options[i].text == ResponsibleArray[j])//throws error here { GipRemoveSelectedItems(ctl00_m_g_6ad915a8_68ea_4c76_b67a_ad1215320288_ff391_ctl00_ctl00_MultiLookupPicker_m); } } } }

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  • ? and function javascript

    - by Rixius
    is there any way to map the ? key to the function keyword? so that these work: var rFalse = ?() { return false; } (?(){ var str = "i'm in a closure"; }()); window.onload = ?() { alert('window loaded'); } I know that they are attempting to put a shortened function keyword in ecmascript v6, but I'm wondering if it is possible to do it now.

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  • Reverse rdesktop or VNC overlay image!

    - by carlesso
    Hi all. I've got a central server (linux based) and many clients (Windows XP Embedded, afaik) in public places around my country. I need to have these clients to connect to the server with a "reverse" tunnel, that is to say that I need to control the clients from the server but the connection is initialized by clients. The requirement is that, during the connection, an overlay image (or something like that, like a modified version of login screen) is displayed. Some stuff like "Work In Progress". My first idea was to use vncviewer -listen and vnc in reverse mode, but cannot understand how to obfuscate the work I'm doing. Other idea was to use rdesktop in "reverse" mode, but it seems it does not support it. Using rdekstop reverse seems the nicest solution (I can login back the user was in before connection, the login manager - which I can modified - is displayed), but any hint will be appreciated! Thanks in advance!

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  • Single click handler for all buttons in Javascript? Is it a pattern? Whats the benefit?

    - by Hasan Khan
    I have been told that when there are multiple buttons on the page for same purpose but targeting different item e.g. delete item on a grid of items, they say it is recommended to just register for click handler only on the top most element like 'body' and check what was clicked instead of hooking up click with every delete button. Whats the benefit of this? Creating more handlers causes problems? Is it an optimization of some sort? Is it a pattern? Does it have anything to do with performance? Where can I read more about it?

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  • New JavaScript Editor

    - by Petr
    I did not write a blog post here for a few weeks. I think the last my post was  about releasing NetBeans 7.1 in the beginning of January. The reason is not that I would change the job:), but that I have concentrated on new JavaScript support/editor. The new JavaScript editor is written basically from scratch. The answer for the question "Why from beginning again, why do you just improve the old one?" is not easy and the decision has more aspects. One of the main reasons is that the old support was written 4 years ago and the architecture is limited. Also during the time, the APIs were changed and it was very hard to keep the editor up to date. Also there is a license issue etc. In short, it is time to rewrite the old JS editor.  We build up strong community about the PHP support in NetBeans and because many PHP developers also write JavaScript code I would like to ask you for a help. There is a continual PHP build with the new JavaScript support. You can download the result of the builds here. It's a zip file. You can unzip the file anywhere, where you want. I recommend to run the build with the new userdir, to avoid damaging your current userdir. It shouldn't happened, but just to be sure:). You can achieve this through the switch --userdir. So start the unzipped file from command line from the folder, where you unzipped it, can be done with this command on unix: bin/netbeans.sh --userdir /path/to/new/userdir and on windows: bin\netbeans.exe --userdir D:\path\to\new\userdir For the developers who use continual php build already, it's well known. There is also full IDE build with the new JavaScript support for people, who need more than only PHP support.  Because the builds with the new JavaScript editor is created from a branch, there are not nightly builds available. They will be, when we merge the branch to the trunk, but so far we have to work only with the mentioned continual build. We will merge our branch after branching NetBeans 7.2 from trunk. This is also answer for the question, what release of NetBeans will contain the new JS support. It should be the release after NetBeans 7.2. I'm asking you whether you could play with the builds or better, could work in the builds with new JavaScript support and tell us every issue that you run in. It can be everything what doesn't fit you, something doesn't work as you expected, something is slow, you want change the behaviour of a feature etc. Your input / comments are very important for us and it will help us to achieve the new JavaScript support that you need.  The best way how to communicate issues is through our Bugzilla, because it is simple to track them. Sure you can write comment here:), but still I prefer Bugzilla for any issue. You can click here (you should be already log in Bugzilla), a form for the new JavaScript issue is opened, with pre-filled component Editor and NO72 keyword. I will write about the single features later, but now I will mentioned a few features that should work in better way than in the old support.  Syntactic and semantic colouring Navigator Mark Occurrences and GoTo Declaration  Code Completion Code Completion is invoked through keyboard shortcut CTRL+SPACE. The first invocation offers items that are found through a source model. Almost all editor features are based on the model, that is build from source code. There is a lot of work on the model yet, but it should offer better results. When the pop up window with code completion items is open and you press CTRL+SPACE again, then the code completion offers all elements that are in the project. In the pictures all elements that starts with letter 't'. Formatter with many options and more :) A few features are not still implemented that are supported in the old JavaScript support (for example jQuery support), but we are adding this features ASAP.

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  • Is there a way to catch assignments to or reads from an undefined property in JavaScript?

    - by avri
    JavaScript implements the noSuchMethod callback function for JavaScript Objects. This function is called whenever JavaScript tries to execute an undefined method of an Object. I would like to set a callback function to an Object that will be called whenever an undefined property in the Object is accessed or assigned to. I haven't found a noSuchProperty function implemented for JavaScript Objects and I am curios if there is any workaround that will achieve the same result.

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  • What's the best way to pass a PHP variable to Javascript?

    - by Gregory Bolkenstijn
    I currently echo certain variables in hidden input fields and read them out with Javascript whenever I need them. Me and a colleague are now thinking of generating an extra Javascript file with PHP which only contains all variables for Javascript. This way the variables already exist and there is no extra code in the HTML. What are good ways to pass variables from PHP to Javascript? And how does our solution sound?

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  • Javascript: can I call a function in an external file from the main page ?

    - by Patrick
    hi, I'm loading from my main page an external js file, with a function. I have a flash file in the main page invoking the javascript function. Everything worked very well until when the javascript code was in the main file, but when I moved javascript to an external file the function seems not called anymore. So... there is no way to move the javascript code to an external file ? Or any other solution ? thanks

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  • Is external JavaScript source available to scripting context inside HTML page?

    - by John K
    When an external JavaScript file is referenced, <script type="text/javascript" src="js/jquery-1.4.4.min.js"></script> is the JavaScript source (lines of code before interpretation) available from the DOM or window context in the current HTML page? I mean by using only standard JavaScript without any installed components or tools. I know tools like Firebug trace into external source but it's installed on the platform and likely has special ability outside the context of the browser sandbox.

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  • Valid JavaScript code that is NOT valid ActionScript 3.0 code?

    - by knorv
    Most JavaScript code is also syntactically valid ActionScript 3.0 code. However, there are exceptions which leads me to my question: Which constructs/features in JavaScript are syntactically invalid in ActionScript 3.0? Please provide concrete examples of JavaScript code (basic JavaScript code without DOM API usage) that is NOT valid ActionScript 3.0 code.

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  • Using jQuery to Insert a New Database Record

    - by Stephen Walther
    The goal of this blog entry is to explore the easiest way of inserting a new record into a database using jQuery and .NET. I’m going to explore two approaches: using Generic Handlers and using a WCF service (In a future blog entry I’ll take a look at OData and WCF Data Services). Create the ASP.NET Project I’ll start by creating a new empty ASP.NET application with Visual Studio 2010. Select the menu option File, New Project and select the ASP.NET Empty Web Application project template. Setup the Database and Data Model I’ll use my standard MoviesDB.mdf movies database. This database contains one table named Movies that looks like this: I’ll use the ADO.NET Entity Framework to represent my database data: Select the menu option Project, Add New Item and select the ADO.NET Entity Data Model project item. Name the data model MoviesDB.edmx and click the Add button. In the Choose Model Contents step, select Generate from database and click the Next button. In the Choose Your Data Connection step, leave all of the defaults and click the Next button. In the Choose Your Data Objects step, select the Movies table and click the Finish button. Unfortunately, Visual Studio 2010 cannot spell movie correctly :) You need to click on Movy and change the name of the class to Movie. In the Properties window, change the Entity Set Name to Movies. Using a Generic Handler In this section, we’ll use jQuery with an ASP.NET generic handler to insert a new record into the database. A generic handler is similar to an ASP.NET page, but it does not have any of the overhead. It consists of one method named ProcessRequest(). Select the menu option Project, Add New Item and select the Generic Handler project item. Name your new generic handler InsertMovie.ashx and click the Add button. Modify your handler so it looks like Listing 1: Listing 1 – InsertMovie.ashx using System.Web; namespace WebApplication1 { /// <summary> /// Inserts a new movie into the database /// </summary> public class InsertMovie : IHttpHandler { private MoviesDBEntities _dataContext = new MoviesDBEntities(); public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/plain"; // Extract form fields var title = context.Request["title"]; var director = context.Request["director"]; // Create movie to insert var movieToInsert = new Movie { Title = title, Director = director }; // Save new movie to DB _dataContext.AddToMovies(movieToInsert); _dataContext.SaveChanges(); // Return success context.Response.Write("success"); } public bool IsReusable { get { return true; } } } } In Listing 1, the ProcessRequest() method is used to retrieve a title and director from form parameters. Next, a new Movie is created with the form values. Finally, the new movie is saved to the database and the string “success” is returned. Using jQuery with the Generic Handler We can call the InsertMovie.ashx generic handler from jQuery by using the standard jQuery post() method. The following HTML page illustrates how you can retrieve form field values and post the values to the generic handler: Listing 2 – Default.htm <!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"> <head> <title>Add Movie</title> <script src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.js" type="text/javascript"></script> </head> <body> <form> <label>Title:</label> <input name="title" /> <br /> <label>Director:</label> <input name="director" /> </form> <button id="btnAdd">Add Movie</button> <script type="text/javascript"> $("#btnAdd").click(function () { $.post("InsertMovie.ashx", $("form").serialize(), insertCallback); }); function insertCallback(result) { if (result == "success") { alert("Movie added!"); } else { alert("Could not add movie!"); } } </script> </body> </html>     When you open the page in Listing 2 in a web browser, you get a simple HTML form: Notice that the page in Listing 2 includes the jQuery library. The jQuery library is included with the following SCRIPT tag: <script src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.js" type="text/javascript"></script> The jQuery library is included on the Microsoft Ajax CDN so you can always easily include the jQuery library in your applications. You can learn more about the CDN at this website: http://www.asp.net/ajaxLibrary/cdn.ashx When you click the Add Movie button, the jQuery post() method is called to post the form data to the InsertMovie.ashx generic handler. Notice that the form values are serialized into a URL encoded string by calling the jQuery serialize() method. The serialize() method uses the name attribute of form fields and not the id attribute. Notes on this Approach This is a very low-level approach to interacting with .NET through jQuery – but it is simple and it works! And, you don’t need to use any JavaScript libraries in addition to the jQuery library to use this approach. The signature for the jQuery post() callback method looks like this: callback(data, textStatus, XmlHttpRequest) The second parameter, textStatus, returns the HTTP status code from the server. I tried returning different status codes from the generic handler with an eye towards implementing server validation by returning a status code such as 400 Bad Request when validation fails (see http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html ). I finally figured out that the callback is not invoked when the textStatus has any value other than “success”. Using a WCF Service As an alternative to posting to a generic handler, you can create a WCF service. You create a new WCF service by selecting the menu option Project, Add New Item and selecting the Ajax-enabled WCF Service project item. Name your WCF service InsertMovie.svc and click the Add button. Modify the WCF service so that it looks like Listing 3: Listing 3 – InsertMovie.svc using System.ServiceModel; using System.ServiceModel.Activation; namespace WebApplication1 { [ServiceBehavior(IncludeExceptionDetailInFaults=true)] [ServiceContract(Namespace = "")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class MovieService { private MoviesDBEntities _dataContext = new MoviesDBEntities(); [OperationContract] public bool Insert(string title, string director) { // Create movie to insert var movieToInsert = new Movie { Title = title, Director = director }; // Save new movie to DB _dataContext.AddToMovies(movieToInsert); _dataContext.SaveChanges(); // Return movie (with primary key) return true; } } }   The WCF service in Listing 3 uses the Entity Framework to insert a record into the Movies database table. The service always returns the value true. Notice that the service in Listing 3 includes the following attribute: [ServiceBehavior(IncludeExceptionDetailInFaults=true)] You need to include this attribute if you want to get detailed error information back to the client. When you are building an application, you should always include this attribute. When you are ready to release your application, you should remove this attribute for security reasons. Using jQuery with the WCF Service Calling a WCF service from jQuery requires a little more work than calling a generic handler from jQuery. Here are some good blog posts on some of the issues with using jQuery with WCF: http://encosia.com/2008/06/05/3-mistakes-to-avoid-when-using-jquery-with-aspnet-ajax/ http://encosia.com/2008/03/27/using-jquery-to-consume-aspnet-json-web-services/ http://weblogs.asp.net/scottgu/archive/2007/04/04/json-hijacking-and-how-asp-net-ajax-1-0-mitigates-these-attacks.aspx http://www.west-wind.com/Weblog/posts/896411.aspx http://www.west-wind.com/weblog/posts/324917.aspx http://professionalaspnet.com/archive/tags/WCF/default.aspx The primary requirement when calling WCF from jQuery is that the request use JSON: The request must include a content-type:application/json header. Any parameters included with the request must be JSON encoded. Unfortunately, jQuery does not include a method for serializing JSON (Although, oddly, jQuery does include a parseJSON() method for deserializing JSON). Therefore, we need to use an additional library to handle the JSON serialization. The page in Listing 4 illustrates how you can call a WCF service from jQuery. Listing 4 – Default2.aspx <!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"> <head> <title>Add Movie</title> <script src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.js" type="text/javascript"></script> <script src="Scripts/json2.js" type="text/javascript"></script> </head> <body> <form> <label>Title:</label> <input id="title" /> <br /> <label>Director:</label> <input id="director" /> </form> <button id="btnAdd">Add Movie</button> <script type="text/javascript"> $("#btnAdd").click(function () { // Convert the form into an object var data = { title: $("#title").val(), director: $("#director").val() }; // JSONify the data data = JSON.stringify(data); // Post it $.ajax({ type: "POST", contentType: "application/json; charset=utf-8", url: "MovieService.svc/Insert", data: data, dataType: "json", success: insertCallback }); }); function insertCallback(result) { // unwrap result result = result["d"]; if (result === true) { alert("Movie added!"); } else { alert("Could not add movie!"); } } </script> </body> </html> There are several things to notice about Listing 4. First, notice that the page includes both the jQuery library and Douglas Crockford’s JSON2 library: <script src="Scripts/json2.js" type="text/javascript"></script> You need to include the JSON2 library to serialize the form values into JSON. You can download the JSON2 library from the following location: http://www.json.org/js.html When you click the button to submit the form, the form data is converted into a JavaScript object: // Convert the form into an object var data = { title: $("#title").val(), director: $("#director").val() }; Next, the data is serialized into JSON using the JSON2 library: // JSONify the data var data = JSON.stringify(data); Finally, the form data is posted to the WCF service by calling the jQuery ajax() method: // Post it $.ajax({   type: "POST",   contentType: "application/json; charset=utf-8",   url: "MovieService.svc/Insert",   data: data,   dataType: "json",   success: insertCallback }); You can’t use the standard jQuery post() method because you must set the content-type of the request to be application/json. Otherwise, the WCF service will reject the request for security reasons. For details, see the Scott Guthrie blog post: http://weblogs.asp.net/scottgu/archive/2007/04/04/json-hijacking-and-how-asp-net-ajax-1-0-mitigates-these-attacks.aspx The insertCallback() method is called when the WCF service returns a response. This method looks like this: function insertCallback(result) {   // unwrap result   result = result["d"];   if (result === true) {       alert("Movie added!");   } else {     alert("Could not add movie!");   } } When we called the jQuery ajax() method, we set the dataType to JSON. That causes the jQuery ajax() method to deserialize the response from the WCF service from JSON into a JavaScript object automatically. The following value is passed to the insertCallback method: {"d":true} For security reasons, a WCF service always returns a response with a “d” wrapper. The following line of code removes the “d” wrapper: // unwrap result result = result["d"]; To learn more about the “d” wrapper, I recommend that you read the following blog posts: http://encosia.com/2009/02/10/a-breaking-change-between-versions-of-aspnet-ajax/ http://encosia.com/2009/06/29/never-worry-about-asp-net-ajaxs-d-again/ Summary In this blog entry, I explored two methods of inserting a database record using jQuery and .NET. First, we created a generic handler and called the handler from jQuery. This is a very low-level approach. However, it is a simple approach that works. Next, we looked at how you can call a WCF service using jQuery. This approach required a little more work because you need to serialize objects into JSON. We used the JSON2 library to perform the serialization. In the next blog post, I want to explore how you can use jQuery with OData and WCF Data Services.

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