Search Results

Search found 54188 results on 2168 pages for 'sqlite net'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 66/2168 | < Previous Page | 62 63 64 65 66 67 68 69 70 71 72 73  | Next Page >

  • Setting up ASP.NET structure for code

    - by user1175327
    I've always coded in C# MVC3 when developing web applications. But now i wanted to learn a bit more about developing web sites with just ASP.NET. But now i'm wondering what a good setup for my code would be. For me, an MVC like pattern seems to be a good way to go. But obviously ASP.NET doesn't have any router and controller classes. So i guess people have a different way of setting up their code when they do ASP.NET. So i'm looking for more information on how to get started with this. So not really the basics of ASP.NET, but something that focuses on a good code setup. Any good tutorials/information about this/?

    Read the article

  • Need help with ColdFusion and ASP.NET site [closed]

    - by Michael Stone
    To begin, I wasn't too sure how to title this.. I've got a few questions. First off, I've got a very big site that's in ColdFusion and we've been migrating to ASP.NET C# 4.0 the last 8 months. I've got a team of 7 programmers and no one can seem to figure out these answers, not even our senior C# programmer. We're using Team Foundation Server and we can't figure out how to only push up one small change at time. Right now we're stuck to publishing the entire site and it's causing serious issues. We've currently got the site as a Project and not a Website. We're wondering if that's one issue. I actually think it might be a problem. We're also dealing with an issue where we can't access our regular folders with relative paths. So we're first developing our admin side in .NET and We've got our regular site and then we've got another site within that for our .NET admin tools. By site, I'm referring to them actually being Sites in IIS. This also creates a problem for us when we're creating tools that upload images and want to store them and access them from our parent Site. I'd very much appreciate any advice on how to go about this in the most standardized way. So what I'm hoping for is advise on: -Publishing and managing a site/project in Team Foundation Server. Being able to push up one fix at a time if needed would be GREAT! -Any help figuring out the issuing referencing folders from my .NET child site to my parent ColdFusion site using regular relative paths. "/a/images/b/" would be nice nice instead of only being able to do "/b/images/" We're using ColdFusion 8, C# Asp.NET 4.0/Entity Framework/POCO Templates, and a Windows 2008 R2 Server. Thank you in advance for any help.

    Read the article

  • Access to path denied when saving an image with ASP.NET 4.0 project

    - by user161276
    I have an existing application that was written in .NET 3.5. The piece of code in question is using the FileUpload control and its SaveAs method. Its worked perfectly for the past six months, but I've recently upgraded the project to .NET 4.0 and I'm now receiving an "Access to path (...) is denied" every time the method is called. It works fine locally in dev mode but fails on my prod server. I've upgraded the website to run under .NET 4.0 and I've made sure the account (Network Service) it runs under in the app pool has full control. Other than upgrading to .NET 4.0, nothing has changed for the project. Any ideas or suggestions? Thanks in advance.

    Read the article

  • ASP.NET book for desktop programmer. [closed]

    - by RealityDysfunction
    Fellow programmers, I have been learning C# for a while now, but my ultimate goal is to develop ASP.NET applications. A few ASP.NET books I looked at either start with absolute basics...What is C#? What is a function...or Assume that I have developed web apps in other languages like PHP...I am looking for a book that is tailored for people who already know desktop programming but wish to learn ASP.NET. Did anybody come across such a book? Many Thanks.

    Read the article

  • why developing ASP.NET - MVC?

    - by sam
    Hi Guys, I am new to web development, I am coding some ASP.NET, I checked a lot of examples using MVC in ASP.NET, But I am looking for verbal answers from senior programmers, about why using MVC? can U as seniors and team leaders show me the benefits?? and why not keeping using asp.net webforms? thanks

    Read the article

  • Automated login on ASP.NET website with C#

    - by user293995
    Hi, I have to login with a username / password with a c# program with asp.net form. I have already do that with HttpUtility on PHP website but how to do that with ASP.NET website ? In ASP.NET, I must handle postback and so on... Any ideas ? Thanks in advance Best regards

    Read the article

  • Uploading Files Using ASP.NET Web Forms, Generic Handler and jQuery

    - by bipinjoshi
    In order to upload files from the client machine to the server ASP.NET developers use FileUpload server control. The FileUpload server control essentially renders an INPUT element with its type set to file and allows you to select one or more files. The actual upload operation is performed only when the form is posted to the server. Instead of making a full page postback you can use jQuery to make an Ajax call to the server and POST the selected files to a generic handler (.ashx). The generic handler can then save the files to a specified folder. The remainder of this post shows how this can be accomplished.http://www.bipinjoshi.net/articles/f2a2f1ee-e18a-416b-893e-883c800f83f4.aspx      

    Read the article

  • An Introduction to ASP.NET MVC Extensibility

    Because ASP.NET MVC has been designed with extensibility as its design principle; almost every logical step of the processing pipeline can be replaced with your own implementation. In fact, the best way to develop applications with ASP.NET MVC is to extend the system, Simone starts a series that explains how to implement extensions to ASP.NET MVC, starting with the ones at the beginning of the pipeline (routing extensions) and finishing with the view extensions points.

    Read the article

  • How to incorporate jquery menu with asp.net membership

    - by wonde
    Hi guys, I am using Asp.net menu control for the web site that I am currently building and I am thinking to change to work with jQuery menu. So the current menu (Asp.net menu control) works with asp.net membership as many of knew.And the menu changed based on the role of the user who logged in. Is it possible to change the menu control to jQuery menu,with out affecting the membership functionality ?

    Read the article

  • Which platform to choose from .Net or Java [closed]

    - by SahilMahajanMj
    I know that there is a lot healthy discussion about this topic. but my case is entirely different from these discussions. I have just passed out my graduation. During the graduation period, i had done C#.net and java as well. Now i am working as Android programmer in a company. In the recent times, i have heard a lot about pros and cons of these platforms. What our seniors used to suggest that, ASP.net is a lot better than JSP for website developement. .net provides us lot of in built tools and API's for building powerfull applications. Java's platform independancy has always been issue among them. Security fetures are more in java. .Net has more powerfull IDE's. Now i am a bit confused on which platform to choose from these. I found java better from two, so did i prefer to choose android. Also, the discussion always ends with an issue that java has no scope for job as far has .net does. I would like to hear suggestions on this topic, but it would be better, if you consider indian IT market for this discussion.

    Read the article

  • .NET - Where can I start? [closed]

    - by mustang2009cobra
    I'm a moderately experienced developer with experience developing using a variety of languages. I've done C++, Java, PHP, Javascript, and several other languages. I remember the Java dev stack being rather difficult to dive into, but it's nothing like the endless sea of the .NET framework. I'd like to become experienced in .NET development, as many dev shops are microsoft-centric. But I'm a little unsure as to where the best place to start is. As I already know a bunch of programming languages, I don't really need resources that will help me learn C# or any of the .NET languages as much as I need to learn the development stack, APIs, etc. Any suggestions on the best way to start learning .NET development?

    Read the article

  • Installing mod_mono on Ubuntu: handler doesn't seem to get registered

    - by Trevor Johns
    I'm trying to install mod_mono on Apache 2 (Prefork MPM). I'm using Ubuntu Karmic, and just want an auto-hosting setup (so that any .aspx files are executed, similar to how PHP is normally setup). I did the following to install Mono: $ apt-get install libapache2-mod-mono mono-apache-server2 mono-devel $ a2dismod mod_mono $ a2enmod mod_mono_auto I've confirmed that mod_mono is getting loaded by Apache. However, any .aspx pages I try to load are returned unprocessed and still have an application/x-asp-net MIME type. It's as if the mod_mono handler never gets registered with Apache. Here's the contents of /etc/mod_mono_auto.load: LoadModule mono_module /usr/lib/apache2/modules/mod_mono.so And here's /etc/mod_mono_auto.conf: MonoAutoApplication enabled AddType application/x-asp-net .aspx AddType application/x-asp-net .asmx AddType application/x-asp-net .ashx AddType application/x-asp-net .asax AddType application/x-asp-net .ascx AddType application/x-asp-net .soap AddType application/x-asp-net .rem AddType application/x-asp-net .axd AddType application/x-asp-net .cs AddType application/x-asp-net .config AddType application/x-asp-net .dll DirectoryIndex index.aspx DirectoryIndex Default.aspx DirectoryIndex default.aspx I've even tried setting the handler explicitly: AddHandler mono .aspx .ascx .asax .ashx .config .cs .asmx .asp Nothing seems to help. Any ideas how to get this working?

    Read the article

  • Adding Unobtrusive Validation To MVCContrib Fluent Html

    - by srkirkland
    ASP.NET MVC 3 includes a new unobtrusive validation strategy that utilizes HTML5 data-* attributes to decorate form elements.  Using a combination of jQuery validation and an unobtrusive validation adapter script that comes with MVC 3, those attributes are then turned into client side validation rules. A Quick Introduction to Unobtrusive Validation To quickly show how this works in practice, assume you have the following Order.cs class (think Northwind) [If you are familiar with unobtrusive validation in MVC 3 you can skip to the next section]: public class Order : DomainObject { [DataType(DataType.Date)] public virtual DateTime OrderDate { get; set; }   [Required] [StringLength(12)] public virtual string ShipAddress { get; set; }   [Required] public virtual Customer OrderedBy { get; set; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Note the System.ComponentModel.DataAnnotations attributes, which provide the validation and metadata information used by ASP.NET MVC 3 to determine how to render out these properties.  Now let’s assume we have a form which can edit this Order class, specifically let’s look at the ShipAddress property: @Html.LabelFor(x => x.Order.ShipAddress) @Html.EditorFor(x => x.Order.ShipAddress) @Html.ValidationMessageFor(x => x.Order.ShipAddress) .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now the Html.EditorFor() method is smart enough to look at the ShipAddress attributes and write out the necessary unobtrusive validation html attributes.  Note we could have used Html.TextBoxFor() or even Html.TextBox() and still retained the same results. If we view source on the input box generated by the Html.EditorFor() call, we get the following: <input type="text" value="Rua do Paço, 67" name="Order.ShipAddress" id="Order_ShipAddress" data-val-required="The ShipAddress field is required." data-val-length-max="12" data-val-length="The field ShipAddress must be a string with a maximum length of 12." data-val="true" class="text-box single-line input-validation-error"> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } As you can see, we have data-val-* attributes for both required and length, along with the proper error messages and additional data as necessary (in this case, we have the length-max=”12”). And of course, if we try to submit the form with an invalid value, we get an error on the client: Working with MvcContrib’s Fluent Html The MvcContrib project offers a fluent interface for creating Html elements which I find very expressive and useful, especially when it comes to creating select lists.  Let’s look at a few quick examples: @this.TextBox(x => x.FirstName).Class("required").Label("First Name:") @this.MultiSelect(x => x.UserId).Options(ViewModel.Users) @this.CheckBox("enabled").LabelAfter("Enabled").Title("Click to enable.").Styles(vertical_align => "middle")   @(this.Select("Order.OrderedBy").Options(Model.Customers, x => x.Id, x => x.CompanyName) .Selected(Model.Order.OrderedBy != null ? Model.Order.OrderedBy.Id : "") .FirstOption(null, "--Select A Company--") .HideFirstOptionWhen(Model.Order.OrderedBy != null) .Label("Ordered By:")) .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } These fluent html helpers create the normal html you would expect, and I think they make life a lot easier and more readable when dealing with complex markup or select list data models (look ma: no anonymous objects for creating class names!). Of course, the problem we have now is that MvcContrib’s fluent html helpers don’t know about ASP.NET MVC 3’s unobtrusive validation attributes and thus don’t take part in client validation on your page.  This is not ideal, so I wrote a quick helper method to extend fluent html with the knowledge of what unobtrusive validation attributes to include when they are rendered. Extending MvcContrib’s Fluent Html Before posting the code, there are just a few things you need to know.  The first is that all Fluent Html elements implement the IElement interface (MvcContrib.FluentHtml.Elements.IElement), and the second is that the base System.Web.Mvc.HtmlHelper has been extended with a method called GetUnobtrusiveValidationAttributes which we can use to determine the necessary attributes to include.  With this knowledge we can make quick work of extending fluent html: public static class FluentHtmlExtensions { public static T IncludeUnobtrusiveValidationAttributes<T>(this T element, HtmlHelper htmlHelper) where T : MvcContrib.FluentHtml.Elements.IElement { IDictionary<string, object> validationAttributes = htmlHelper .GetUnobtrusiveValidationAttributes(element.GetAttr("name"));   foreach (var validationAttribute in validationAttributes) { element.SetAttr(validationAttribute.Key, validationAttribute.Value); }   return element; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The code is pretty straight forward – basically we use a passed HtmlHelper to get a list of validation attributes for the current element and then add each of the returned attributes to the element to be rendered. The Extension In Action Now let’s get back to the earlier ShipAddress example and see what we’ve accomplished.  First we will use a fluent html helper to render out the ship address text input (this is the ‘before’ case): @this.TextBox("Order.ShipAddress").Label("Ship Address:").Class("class-name") .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } And the resulting HTML: <label id="Order_ShipAddress_Label" for="Order_ShipAddress">Ship Address:</label> <input type="text" value="Rua do Paço, 67" name="Order.ShipAddress" id="Order_ShipAddress" class="class-name"> Now let’s do the same thing except here we’ll use the newly written extension method: @this.TextBox("Order.ShipAddress").Label("Ship Address:") .Class("class-name").IncludeUnobtrusiveValidationAttributes(Html) .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } And the resulting HTML: <label id="Order_ShipAddress_Label" for="Order_ShipAddress">Ship Address:</label> <input type="text" value="Rua do Paço, 67" name="Order.ShipAddress" id="Order_ShipAddress" data-val-required="The ShipAddress field is required." data-val-length-max="12" data-val-length="The field ShipAddress must be a string with a maximum length of 12." data-val="true" class="class-name"> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Excellent!  Now we can continue to use unobtrusive validation and have the flexibility to use ASP.NET MVC’s Html helpers or MvcContrib’s fluent html helpers interchangeably, and every element will participate in client side validation. Wrap Up Overall I’m happy with this solution, although in the best case scenario MvcContrib would know about unobtrusive validation attributes and include them automatically (of course if it is enabled in the web.config file).  I know that MvcContrib allows you to author global behaviors, but that requires changing the base class of your views, which I am not willing to do. Enjoy!

    Read the article

  • Updating a local sqlite db that is used for local metadata & caching from an service?

    - by Pharaun
    I've searched through the site and haven't found a question/answer that quite answer my question, the closest one I found was: Syncing objects between two disparate systems best approach. Anyway to begun, because there is no RSS feeds available, I'm screen scrapping a webpage, hence it does a fetch then it goes through the webpage to scrap out all of the information that I'm interested in and dumps that information into a sqlite database so that I can query the information at my leisure without doing repeat fetching from the website. However I'm also storing various metadata on the data itself that is stored in the sqlite db, such as: have I looked at the data, is the data new/old, bookmark to a chunk of data (Think of it as a collection of unrelated data, and the bookmark is just a pointer to where I am in processing/reading of the said data). So right now my current problem is trying to figure out how to update the local sqlite database with new data and/or changed data from the website in a manner that is effective and straightforward. Here's my current idea: Download the page itself Create a temporary table for the parsed data to go into Do a comparison between the official and the temporary table and copy updates and/or new information to the official table This process seems kind of complicated because I would have to figure out how to determine if the data in the temporary table is new, updated, or unchanged. So I am wondering if there isn't a better approach or if anyone has any suggestion on how to architecture/structure such system?

    Read the article

  • Why is PHP5 SQLite PDO silently failing on DB connection?

    - by danieltalsky
    I have no idea why my code is failing silently. PDO and PDO SQLite are confirmed loaded. Errors are turned on and OTHER errors display. The SQLite file exists. Perms are set correctly. If I change the filename, PHP actually DOES create the file but still fails silently. No output or commands are excecuted after the "$dbh = new PDO($db_conn);" command. I'm not sure what else I can possibly do to troubleshoot. What else... this is on Modwest shared hosting. ABOUT TO RUN <?php // Destination $db_name = '/confirmed/valid/path/DBName.db3'; $db_conn = 'sqlite:' . $db_name; try { var_dump($db_conn); $dbh = new PDO($db_conn); $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); } catch (Exception $e) { exit("Failed to open database: {$e->getMessage()} \n" ); } ?> THIS NEVER OUTPUTS! sdf

    Read the article

  • Asp.net tips and tricks

    - by ybbest
    Asp.net tips and tricks Here is a summary of articles I found very useful over the years while I am working on asp.net TRULY Understanding View state http://weblogs.asp.net/infinitiesloop/archive/2006/08/03/Truly-Understanding-Viewstate.aspx TRULY Understanding Dynamic Controls http://weblogs.asp.net/infinitiesloop/archive/2006/08/25/TRULY-Understanding-Dynamic-Controls-_2800_Part-1_2900_.aspx ASP.Net 2.0 – Master Pages: Tips, Tricks, and Traps http://odetocode.com/articles/450.aspx ASP.NET Tip – Use The Label Control Correctly http://haacked.com/archive/2007/02/15/asp.net_tip_-_use_the_label_control_correctly.aspx Asp.net httphandlers http://www.michaelflanakin.com/Articles/NET/NET1x/ImplementingHTTPHandlers/tabid/173/Default.aspx http://support.microsoft.com/default.aspx?scid=kb;EN-US;308001 http://msdn.microsoft.com/en-us/library/ms972974.aspx Asp.net ajax http://encosia.com/ ASP.NET 2.0 Tips, Tricks, Recipes and Gotchas http://weblogs.asp.net/scottgu/pages/ASP.NET-2.0-Tips_2C00_-Tricks_2C00_-Recipes-and-Gotchas.aspx Mastering Page-UserControl Communication http://www.codeproject.com/KB/user-controls/Page_UserControl.aspx Comparing Web Site Projects and Web Application Projects Web Deployment Projects .NET Radio Show http://www.dotnetrocks.com/ Herdingcode http://herdingcode.com/ Clean Code talk http://www.objectmentor.com/videos/video_index.html .NET Video Show http://www.dnrtv.com/ .Net User group http://chicagoalt.net/home http://exposureroom.com/members/RIAViewMirror.aspx/assets/ FAQ Why should you remove unnecessary C# using directives? http://stackoverflow.com/questions/136278/why-should-you-remove-unnecessary-c-using-directives http://stackoverflow.com/questions/2009471/what-is-the-benefit-of-removing-redundant-imports-in-vb-net-or-using-in-c-file http://codeclimber.net.nz/archive/2009/12/30/best-of-2009-the-5-most-popular-posts.aspx

    Read the article

  • Displaying an image on a LED matrix with a Netduino

    - by Bertrand Le Roy
    In the previous post, we’ve been flipping bits manually on three ports of the Netduino to simulate the data, clock and latch pins that a shift register expected. We did all that in order to control one line of a LED matrix and create a simple Knight Rider effect. It was rightly pointed out in the comments that the Netduino has built-in knowledge of the sort of serial protocol that this shift register understands through a feature called SPI. That will of course make our code a whole lot simpler, but it will also make it a whole lot faster: writing to the Netduino ports is actually not that fast, whereas SPI is very, very fast. Unfortunately, the Netduino documentation for SPI is severely lacking. Instead, we’ve been reliably using the documentation for the Fez, another .NET microcontroller. To send data through SPI, we’ll just need  to move a few wires around and update the code. SPI uses pin D11 for writing, pin D12 for reading (which we won’t do) and pin D13 for the clock. The latch pin is a parameter that can be set by the user. This is very close to the wiring we had before (data on D11, clock on D12 and latch on D13). We just have to move the latch from D13 to D10, and the clock from D12 to D13. The code that controls the shift register has slimmed down considerably with that change. Here is the new version, which I invite you to compare with what we had before: public class ShiftRegister74HC595 { protected SPI Spi; public ShiftRegister74HC595(Cpu.Pin latchPin) : this(latchPin, SPI.SPI_module.SPI1) { } public ShiftRegister74HC595(Cpu.Pin latchPin, SPI.SPI_module spiModule) { var spiConfig = new SPI.Configuration( SPI_mod: spiModule, ChipSelect_Port: latchPin, ChipSelect_ActiveState: false, ChipSelect_SetupTime: 0, ChipSelect_HoldTime: 0, Clock_IdleState: false, Clock_Edge: true, Clock_RateKHz: 1000 ); Spi = new SPI(spiConfig); } public void Write(byte buffer) { Spi.Write(new[] {buffer}); } } All we have to do here is configure SPI. The write method couldn’t be any simpler. Everything is now handled in hardware by the Netduino. We set the frequency to 1MHz, which is largely sufficient for what we’ll be doing, but it could potentially go much higher. The shift register addresses the columns of the matrix. The rows are directly wired to ports D0 to D7 of the Netduino. The code writes to only one of those eight lines at a time, which will make it fast enough. The way an image is displayed is that we light the lines one after the other so fast that persistence of vision will give the illusion of a stable image: foreach (var bitmap in matrix.MatrixBitmap) { matrix.OnRow(row, bitmap, true); matrix.OnRow(row, bitmap, false); row++; } Now there is a twist here: we need to run this code as fast as possible in order to display the image with as little flicker as possible, but we’ll eventually have other things to do. In other words, we need the code driving the display to run in the background, except when we want to change what’s being displayed. Fortunately, the .NET Micro Framework supports multithreading. In our implementation, we’ve added an Initialize method that spins a new thread that is tied to the specific instance of the matrix it’s being called on. public LedMatrix Initialize() { DisplayThread = new Thread(() => DoDisplay(this)); DisplayThread.Start(); return this; } I quite like this way to spin a thread. As you may know, there is another, built-in way to contextualize a thread by passing an object into the Start method. For the method to work, the thread must have been constructed with a ParameterizedThreadStart delegate, which takes one parameter of type object. I like to use object as little as possible, so instead I’m constructing a closure with a Lambda, currying it with the current instance. This way, everything remains strongly-typed and there’s no casting to do. Note that this method would extend perfectly to several parameters. Of note as well is the return value of Initialize, a common technique to add some fluency to the API and enabling the matrix to be instantiated and initialized in a single line: using (var matrix = new LedMS88SR74HC595().Initialize()) The “using” in the previous line is because we have implemented IDisposable so that the matrix kills the thread and clears the display when the user code is done with it: public void Dispose() { Clear(); DisplayThread.Abort(); } Thanks to the multi-threaded version of the matrix driver class, we can treat the display as a simple bitmap with a very synchronous programming model: matrix.Set(someimage); while (button.Read()) { Thread.Sleep(10); } Here, the call into Set returns immediately and from the moment the bitmap is set, the background display thread will constantly continue refreshing no matter what happens in the main thread. That enables us to wait or read a button’s port on the main thread knowing that the current image will continue displaying unperturbed and without requiring manual refreshing. We’ve effectively hidden the implementation of the display behind a convenient, synchronous-looking API. Pretty neat, eh? Before I wrap up this post, I want to talk about one small caveat of using SPI rather than driving the shift register directly: when we got to the point where we could actually display images, we noticed that they were a mirror image of what we were sending in. Oh noes! Well, the reason for it is that SPI is sending the bits in a big-endian fashion, in other words backwards. Now sure you could fix that in software by writing some bit-level code to reverse the bits we’re sending in, but there is a far more efficient solution than that. We are doing hardware here, so we can simply reverse the order in which the outputs of the shift register are connected to the columns of the matrix. That’s switching 8 wires around once, as compared to doing bit operations every time we send a line to display. All right, so bringing it all together, here is the code we need to write to display two images in succession, separated by a press on the board’s button: var button = new InputPort(Pins.ONBOARD_SW1, false, Port.ResistorMode.Disabled); using (var matrix = new LedMS88SR74HC595().Initialize()) { // Oh, prototype is so sad! var sad = new byte[] { 0x66, 0x24, 0x00, 0x18, 0x00, 0x3C, 0x42, 0x81 }; DisplayAndWait(sad, matrix, button); // Let's make it smile! var smile = new byte[] { 0x42, 0x18, 0x18, 0x81, 0x7E, 0x3C, 0x18, 0x00 }; DisplayAndWait(smile, matrix, button); } And here is a video of the prototype running: The prototype in action I’ve added an artificial delay between the display of each row of the matrix to clearly show what’s otherwise happening very fast. This way, you can clearly see each of the two images being displayed line by line. Next time, we’ll do no hardware changes, focusing instead on building a nice programming model for the matrix, with sprites, text and hardware scrolling. Fun stuff. By the way, can any of my reader guess where we’re going with all that? The code for this prototype can be downloaded here: http://weblogs.asp.net/blogs/bleroy/Samples/NetduinoLedMatrixDriver.zip

    Read the article

  • Tulsa SharePoint Interest Group – Meeting Reminder

    - by dmccollough
    Just a quick reminder that the Tulsa SharePoint Interest Group is having it’s monthly meeting this coming Monday April 12th @6:00 PM.   Please come see Corey Roth’s presentation on SharePoint 2010 Business Connectivity Services   We are going to be giving away some GREAT prizes XBox 360 – Halo 3 ODST Telerik Premium Collection ($1,300.00 value) ReSharper ($199.00 value) SQL Sets ($149.00 value) 64 Bit Windows 7 Infragistics NetAdvantage for .NET Platform ($1,195.00 value) You can click here for more information. You can click here to RSVP for the meeting.

    Read the article

  • Speaking at Microsoft's Duth DevDays

    - by gsusx
    Last week I had the pleasure of presenting two sessions at Microsoft's Dutch DevDays at Den Hague. On Tuesday I presented a sessions about how to implement real world RESTFul services patterns using WCF, WCF Data Services and ASP.NET MVC2. During that session I showed a total of 15 small demos that highlighted how to implement key aspects of RESTful solutions such as Security, LowREST clients, URI modeling, Validation, Error Handling, etc. As part of those demos I used the OAuth implementation created...(read more)

    Read the article

  • Using delegates in C# (Part 2)

    - by rajbk
    Part 1 of this post can be read here. We are now about to see the different syntaxes for invoking a delegate and some c# syntactic sugar which allows you to code faster. We have the following console application. 1: public delegate double Operation(double x, double y); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: Operation op1 = new Operation(Division); 9: double result = op1.Invoke(10, 5); 10: 11: Console.WriteLine(result); 12: Console.ReadLine(); 13: } 14: 15: static double Division(double x, double y) { 16: return x / y; 17: } 18: } Line 1 defines a delegate type called Operation with input parameters (double x, double y) and a return type of double. On Line 8, we create an instance of this delegate and set the target to be a static method called Division (Line 15) On Line 9, we invoke the delegate (one entry in the invocation list). The program outputs 5 when run. The language provides shortcuts for creating a delegate and invoking it (see line 9 and 11). Line 9 is a syntactical shortcut for creating an instance of the Delegate. The C# compiler will infer on its own what the delegate type is and produces intermediate language that creates a new instance of that delegate. Line 11 uses a a syntactical shortcut for invoking the delegate by removing the Invoke method. The compiler sees the line and generates intermediate language which invokes the delegate. When this code is compiled, the generated IL will look exactly like the IL of the compiled code above. 1: public delegate double Operation(double x, double y); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: //shortcut constructor syntax 9: Operation op1 = Division; 10: //shortcut invoke syntax 11: double result = op1(10, 2); 12: 13: Console.WriteLine(result); 14: Console.ReadLine(); 15: } 16: 17: static double Division(double x, double y) { 18: return x / y; 19: } 20: } C# 2.0 introduced Anonymous Methods. Anonymous methods avoid the need to create a separate method that contains the same signature as the delegate type. Instead you write the method body in-line. There is an interesting fact about Anonymous methods and closures which won’t be covered here. Use your favorite search engine ;-)We rewrite our code to use anonymous methods (see line 9): 1: public delegate double Operation(double x, double y); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: //Anonymous method 9: Operation op1 = delegate(double x, double y) { 10: return x / y; 11: }; 12: double result = op1(10, 2); 13: 14: Console.WriteLine(result); 15: Console.ReadLine(); 16: } 17: 18: static double Division(double x, double y) { 19: return x / y; 20: } 21: } We could rewrite our delegate to be of a generic type like so (see line 2 and line 9). You will see why soon. 1: //Generic delegate 2: public delegate T Operation<T>(T x, T y); 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: Operation<double> op1 = delegate(double x, double y) { 10: return x / y; 11: }; 12: double result = op1(10, 2); 13: 14: Console.WriteLine(result); 15: Console.ReadLine(); 16: } 17: 18: static double Division(double x, double y) { 19: return x / y; 20: } 21: } The .NET 3.5 framework introduced a whole set of predefined delegates for us including public delegate TResult Func<T1, T2, TResult>(T1 arg1, T2 arg2); Our code can be modified to use this delegate instead of the one we declared. Our delegate declaration has been removed and line 7 has been changed to use the Func delegate type. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: //Func is a delegate defined in the .NET 3.5 framework 7: Func<double, double, double> op1 = delegate (double x, double y) { 8: return x / y; 9: }; 10: double result = op1(10, 2); 11: 12: Console.WriteLine(result); 13: Console.ReadLine(); 14: } 15: 16: static double Division(double x, double y) { 17: return x / y; 18: } 19: } .NET 3.5 also introduced lambda expressions. A lambda expression is an anonymous function that can contain expressions and statements, and can be used to create delegates or expression tree types. We change our code to use lambda expressions. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: //lambda expression 7: Func<double, double, double> op1 = (x, y) => x / y; 8: double result = op1(10, 2); 9: 10: Console.WriteLine(result); 11: Console.ReadLine(); 12: } 13: 14: static double Division(double x, double y) { 15: return x / y; 16: } 17: } C# 3.0 introduced the keyword var (implicitly typed local variable) where the type of the variable is inferred based on the type of the associated initializer expression. We can rewrite our code to use var as shown below (line 7).  The implicitly typed local variable op1 is inferred to be a delegate of type Func<double, double, double> at compile time. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: //implicitly typed local variable 7: var op1 = (x, y) => x / y; 8: double result = op1(10, 2); 9: 10: Console.WriteLine(result); 11: Console.ReadLine(); 12: } 13: 14: static double Division(double x, double y) { 15: return x / y; 16: } 17: } You have seen how we can write code in fewer lines by using a combination of the Func delegate type, implicitly typed local variables and lambda expressions.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 62 63 64 65 66 67 68 69 70 71 72 73  | Next Page >