I have posted an updated version

Given my plans to rather sooner than later upgrade my server to IIS7, I am currently switching all applications to ASP.NET 2.0 in preparation of this move. But there was nGallery, which I used all over the place when I needed a photo gallery...

Today I decided it was about time to do something about it, and gave converting nGallery to .NET 2.0 a try (actually all the projects target .NET Framework 3.5). Turns out it took me roundabout two hours for this whole endeavour. To save everybody else time, here is my VS2008 solution tree:

nGalleryTNG.zip (2.92 MB)

What is changed compared to the original nGallery 1.6.1 for ASP.NET 1.1? Here is a somewhat complete laundry list:

• Converted it to a Web Application project
• Placed all third party source code in the ThirdParty folder. That way I can always change and recompile if necessary.
• Took all static images from the \photos directories and put them into \images. No more mixing the photo handler & photo cache with the Web site's images.
• The album handler is now being abused in Application_BeginRequest, plus it now uses RewritePath. Fixes the darn Server.Transfer errors.
• Moved the configuration of nGallery from the data folder to App_Data. Other than that: no configuration changes.

I did not switch to ASP.NET 2.0 master pages, it still uses the old user control approach. But after all, I only needed it in a working fashion for 2.0+.

Note: I only tested the XML-based storage because that's how I use nGallery. The SQL-storage has received no testing whatsoever!

Download Web site files only: nGalleryTNG_WebSite.zip (924.39 KB)

Last Tuesday, I held the talk "Advanced Code Access Security" at UG Styria in Graz. This talk was originally part of the MSDN Security Briefings held in Austria earlier this year, for which MS Austria had asked MVPs to help create and deliver security content. Advanced CAS seemed an interesting enough developer topic to re-run at user groups, and Mario (the author of this session) has allowed me to publish the slide deck and demos for the general public.

AdvancedCodeAccessSecurity.pdf (4542 KB)

AdvancedCAS.zip (599.6 KB)

Please note that I have published only demos four (setting CAS via setup) and six (using CAS in addin application) - those are the "completed" versions of the demos.

Beta 1 of SharpDevelop2 2.1 is available for download. While I was putting together the annoucement for v2.1 yesterday, I realized that for a point release, we really managed to put in a lot of new cool features:

• FxCop Support
• Component Inspector
• WiX Support
• Incremental Search
• Code Navigation History
• List Data Sources in SharpReport
• XPath Queries
• Code Completion for Different Frameworks
• GoTo XML Schema Definition
• Targeting Different Frameworks
• Hosting of SharpDevelop in 3rd Party Applications

A couple of WOW features (for me, at least): Not only can you compile an application for different versions of .NET, you also get version-specific code completion support. Another cool one is that you can host SharpDevelop in your application, providing your application a "macro editor" (on steroids I might add) with full .NET support. And to pick a third, code analysis rounds out our professional offering in addition to code coverage as well as unit testing.

Two features did not make it for the Beta 1 announcement as they don't yet cover all the scenarios we are hoping for: integrated Subversion support (yeah!) and targetting the Compact Framework for Windows CE devices. Those slipped silently into this release.

As you can see, SharpDevelop is ever growing and the developers working on it can be rightly proud of their achievements!

Finally, a kind of "call to action": let us know what you think! Not only in our forums, but also in your blogs, communities, et cetera. We need your feedback regarding feature set, stability, and much more.

Disclaimer: I am the PM for the #develop project.

After almost two years in development, the #develop team has shipped version 2.0 of its open source integrated development environment (IDE) SharpDevelop2. The new version supports the .sln / .*proj project file formats of Visual Studio 2005, therefore you can open and edit existing projects inside SharpDevelop2. The team however does not view SharpDevelop2 as a competitor for the Express line of products (comparison) from Microsoft, but it aims at software developers that need best of breed tools for their software development process - like unit testing, code coverage, documentation generation and more. In the same vein, version 2.1 will complement those existing features with integrated source code control, code analysis tools as well component testing.

SharpDevelop2 is especially well-suited for developers that chose the Boo language, because SharpDevelop2 offers first-class support for code completion as well as the Windows Forms designer. Aside from this unique selling point there a couple of smaller but nonetheless productivity-enhancing features in version 2.0: code conversion (eg VB.NET to C#, but see for yourself), support for Mono, documentation preview, RegEx compilation und quite a few more.

A lot of the features are owed to the ease of integration and extensibility provided by the addin system found in SharpDevelop2. This addin system can be used by developers in their own application - this being the reason for the rather unconventional license choice for SharpDevelop2: LGPL instead of GPL, which is much more common for development tools such as #develop. Re-use by third parties has been the driving factor to change the license.

Thanks to all the contributors that made SharpDevelop2 a reality, especially the technical lead on the 2.x effort, Daniel Grunwald.

As promised, here is the list of links / articles / samples that I used for preparing my talk "Build Provider in ASP.NET 2.0":

• Provider Toolkit
• Extending ASP.NET 2.0 Part I: Creating Custom Build Providers
• Jaw-dropping experience with custom build providers
• DLINQ ASP.NET Build Provider and DLINQ DataSource (Andres sent me a newer version for the May CTP)
• RSS Toolkit (sports two build providers, one for .rssdl, the other for .rss)
• Web Services Contract First: Drop Schema in app_code with a Custom Build Provider

Hope you will find those useful.

Six labs, both available in C# and VB.NET. Download (nuff said)

If you ever consider using NGen with your .NET applications, then you simply MUST read the article The Performance Benefits of NGen in the current issue of MSDN Magazine. It can't get any more authoritative than that (the author Surupa Biswas works on the runtime's back-end compiler and focuses primarily on pre-compilation technologies).

On my flight to Seattle today (or yesterday, depending on the time zone) I started to read Professional ASP.NET 2.0 Security, Membership, and Role Management by Stefan Schackow. The book definitely is a must-have for every ASP.NET developer, even if you decide to read one chapter only: A Matter of Trust (#3). This one will save you loads of time when you have to deploy an application into non-full trust environments. However, the other chapters are worthwhile too, like #2 which details exactly which identity is used when by what part of the engine. Bottomline: highly recommended reading.

Will be there Wednesday & Thursday as ATE (Ask the Experts), so drop by in the experts zone and say hello!

Yesterday, I picked up on an old code piece of mine - sending images to the client via an HttpHandler. Why in the world would you implement that with a handler when there is http.sys kernel mode caching? Well, I had a few unique constraints:

• the images had to live outside the Web root and any of its vroots
• the image names had to be concealed because the naming would give away information, and renaming the images prior to publishing on the Web was out of the question

Now, a common approach to sending images from a certain directory (leaving requirement #2 by the wayside for the moment) would be this:

image.aspx?image=iamthebest.jpg

So what is wrong with this approach? First and foremost using an ASP.NET page. The page lifecycle is a drain on performance and throughput, because you simply don't need it. That sorts out why I chose to go with an HTTP handler.

Secondly, somebody could DOS your server. You heard me right. For the background, check the article Trap Alert: Files that aren't. A .NET version (managed C++) of this checker can be found in this download (the article Dateityp-Ermittlung in Managed C++ is only available in German).

How do you get around this issue? Well, how about reading the directory up front, and instead of having the filename in the URL, send the hash! When the image is requested, take the hash and look up the corresponding file, presto. In addition you get one security feature for free: no directory traversals can be hidden in your code.

When I uncovered the code yesterday, I decided to rewrite it for more general use. So what do you get?

• The ImageCacheControls project: it contains the ImageCache class, which does most of the heavy lifting. In addition, you get an ImageCacheControl server control, as well as the implementation of the HTTP handler. (Don't forget to check out the Readme.txt for the latest on feature set and known issues)
• The Web project: a rather simple Web site with demo files in it. The file I want to direct your attention to is Image.ashx. This is the one file - aside from the control project binaries - that needs to be copied to your projects to get started with ImageCache. Note that I made it easy to work with C# (default) or VB.NET.

Usage of ImageCache is demonstrated in default.aspx.cs plus the source code of default.aspx (design time of the control does not work, known issue).

The code behind looks like this (CreateMapping loads the directory contents, initializes the hash to file name map, stores it into the cache):

using ChrisOnNET.ImageCache;

public partial class _Default : System.Web.UI.Page
{
   protected void Page_Load(object sender, EventArgs e)
   {
      // normally, this would be done in global.asax
      ImageCache.CreateMapping("demo", Server.MapPath("~/TestImages/"));

      // the DIY approach to rendering the image tag
      string testHash = ImageCache.GetHashForFile("026.jpg", "demo");
      Response.Write("<image src=\"Image.ashx?bucket=" +
         "demo" +
         "&image=" +
         Server.UrlEncode(testHash) +
         "\" />");

      // the elegant approach to rendering the image tag
      Response.Write("<image src=\"" + ImageCache.GenerateUrl("036.jpg", "demo") +
      "\" />");

      // see HTML source for server control approach (Design time not working, known issue)
   }
}

Rendering Image tags in Page_Load isn't nice, but after all it is only intended to show the functionality. Most likely you are going to use the declarative ImageCacheControl anyways:

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%@ Register Assembly="ImageCacheControls" Namespace="ChrisOnNET.ImageCache" TagPrefix="cc1" %>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <br />Using the ImageCacheControl:&nbsp;
        <cc1:ImageCacheControl ID="ImageCacheControl1" 
            Bucket="demo"
            FileName="026.jpg"
            runat="server" />
    </div>
    </form>
</body>
</html>

That's basically it. Let me know what you think.

ImageCacheTakeOne.zip (59.55 KB)

New runtime components are available which are compatible with the release versions of .NET Framework 2.0, Visual Studio 2005, as well as Office "12" Beta 1 (which I don't have anyways).

Today, a member of our German .NET community asked if it is possible to programmatically query the Google page rank. He had seen it done in PHP (here on the Google Community site), but didn't have time / PHP skills to translate it. All I found on a rather shallow search was PullRank, which I'd describe as non-fit for server use.

So I decided to set out to convert the PHP sample. Being PHP-challenged myself, I decided to give the PHP to ASP.NET Migration Assistant a shot. Whoha! That converted code is the most convoluted contraption to be called code I have seen - ever. I tried to get it to run, but failed because the conversion left me with some loose ends.

Instead of giving in, I contacted Christian Wenz to lend me a hand because he has some PHP experience. He thankfully hosted an "annotated" version of the PHP script so I could look at the output of various stages to test my solution with known-good values. That was most helpful.

Instead of doing a Web site demo application with everything intertwined, I split up the project into two - GPRDotNet being a DLL assembly project you can reference in any type of .NET application (Windows Forms, Web Forms, you name it), as well as a simple Web frontend to demo the usage: DemoSite.

Querying the page rank is really simple - the following snippet is the code from the "Check PageRank" button event handler:

protected void doCheckPageRank_Click(object sender, EventArgs e)
{
  GooglePageRank pr = new GooglePageRank();

  string url = webSiteUrl.Text;

  try
  {
    string rank = pr.GetRank(url);
    thePageRank.Text = rank;
  }
  catch (Exception ex)
  {
    // this is rather chatty (telling the end user everything *IS* a bad idea)
    thePageRank.Text = "Requesting the page rank failed. Reason: " + ex.ToString();
  }
}

I want to emphasize that the code for the GooglePageRank class is a rather quick & dirty port of the PHP code and that it does not contain the necessary error handling you would expect for a server-side library. After all, it is just a proof of concept for our community.

Finally, here is the source code: PageRank.zip (26.89 KB)

If you find errors, please leave a blog comment so others know about improvements. Thanks!

Next week, I will be in Rosenheim, Germany for the ADC 2005. I'll be teaching the Visual Studio 2005 Team System Hands-on workshop (Tuesday as well as Friday), plus doing two talks during the main conference: IIS 7 and ASP.NET 2.0 Health Monitoring. See you there!

You need: Visual Studio 2005, IIS 6.0 and Visual Studio 2005 Web Deployment Projects (Beta Preview). Of course, the .NET Framework 2.0 should be installed.

The site has one simple page: Convert.aspx (C#, separate code file):

As you can see, this page is being run with the ASP.NET Development Web Server. Also works fine with IIS 6.0.

Next, let's add a deployment project to our Web project:

Build it, and in IIS, create a new application and map it to the Debug directory. Execute the page:

Oopsie, what the hell happened here? The answer can be found by digging into the Temporary ASP.NET Files directory:

Let's have a look at the generated vs precompiled assemblies in ILDasm:

So what's the difference? Well, it happens that by default on-demand compilation and precompilation behave differently in the way the pages (page classes) are stitched together. In one case we have a quasi-random name, and in the other we have the class name as it was set in our Convert.aspx - Convert. And this rather obviously clashes with System.Convert (I have a certain talent on picking about the single problematic name).

Why is the Convert name retained? Look in Property Tabs for the deployment project:

By default "Allow this precompiled site to be updatable" is checked - which after all is very useful. But not in this specific case where my Convert class clashes with System.Convert...

In my blog entry Crashing Visual Studio 2005 for Fun I described how to crash Visual Studio 2005. Scott Guthrie followed up, and since then I was in permanent contact with team members. After some research, it turned out that it (a) was seemingly reproducible only on my machine, and (b) likely a tooltip issue.

What is going? Well, my machine is equipped with a Matrox P750 and has three monitors attached, spanning a single 3840x1024 "display". This strechted single display is managed by Matrox PowerDesk-HF, and it comes with a couple of desktop settings to make applications play nice on three physical monitors. One of those options is "Prevent tooltip spanning in strechted mode":

What does this option do? Imagine that I have an application full screen on the middle monitor - without that option turned on, tooltips "overflow" to the monitor to the right (you only see the background image in this screenshot, but that is the 3rd monitor):

Now guess what - once I turn that option on, VS05 crashes the way I described in my previous blog entry. It took me a couple of reboots, configuration from scratch and quite some testing to finally figure out the root cause for this crash.