The problem with beta software libraries

I'll admit it - I'm a serial early-adopter. I was man/mad enough to actually try using Windows Vista Beta 1 for over a whole month as my main workstation OS both at home and at work, and wasn't put off enough not to be considering doing again with Beta 2.

But the problem is compounded when you want to get ahead with new technologies like Windows Communications Foundation (formerly Indigo) - as the library is refined, there are inevitably times when "things change".

For WinFX this seems to have been the norm rather than the exception case - the Windows Workflow Foundation book I bought to help me get going is already out of date in a number of key areas (tho' it does a great job of introducing the concepts). Worknig with WCF, my problem was that the config schema changed between the Jan CTP and the Feb CTP, making the majority the WCF samples on the net incorrect.

To make matters worse, Feb CTP installation does not update the configuration schema, therefore the intellisence will not match the changes that were made in that version - so you don't get any help from VS.

Fortunately, in this post, "WCF configuration schema", Guy Burstein provides not only a reminder about the problem with breaking changes, but also a fix for the problem with a revised schema file to load into Visual Studio.

"forums.microsoft.com to the rescue once again!" shouted Little Cook.

Sahil Malik - blah.winsmarts.com

I've just found the blog of Sahil Malik of Winsmarts.com and in particular a set of postings in which "intend to bring C# 3.0 down to earth".

I'm impressed - by focusing on the smallest language feature possible and covering it in a practical sense, he does a great job of explaining some of the new language features of C# 3.0.

The first 3 postings are:
Part 1: Implicitly Typed Local Variables

Part 2: Anonymous Types

Part 3: Extension Methods

More good stuff to read, and it's well worth subscribing to his blog feed too.

Karl Seguin [MVP] : Have I inherited a disaster?

In his blog on CodeBetter.com, Kark Seguin provides a very useful list of simple searches to run against anyone else's code you have foisted upon you.

To quote from his posting:

"Have I inherited a disaster? I hate taking over someone's bad code. The projects always go on forever and you are forced to follow bad practices to try and string together fixes and features without it all crumbling down. There are some quick, not always 100% accurate, ways to know whether you've inherited a disaster"

It's an excellent read, and a good aide-memoire because it brings such a quick way to check for best (or worst) practice.

You can find the posting here.

.Net code generation strikes again...

In his blog, Stephen Kaufman shows a nicely worked example of using CodeDom to Programmatically Create Windows Workflow Rules.

What makes this interesting is not only does it provide a solution to a real-world problem, but it also re-enforces the underlying nature of .Net - i.e. that .Net code gets compiled into MSIL which the runtime executes.

Definitely worth a read.

Migrating .Net 1.1 to 2.0

Peter Laudati has just posted a great "Four FAQ overview of some of the issues involved with doing a .NET 1.1 to .NET 2.0 migration. The ASP.Net migration guidelines in particular present include a wealth of MSDN and other technical references - including our old favorite the Web Application Project Template.

Excellent stuff.

ATLAS Toolkit Update

Well, my fix didn't make it into the ATLAS Toolkit directly, but the latest refresh does provide a fix for the problem I blogged about before.

The refresh is worth getting not ony for the fixes, but also for the new controls it gives. Probably the most interesting is the Modal Dialog Extender. This little beauty lets you use any panel on a page as a modal dialog, rendered as a floating panel with the rest of the page grayed out and inaccessible. Very nice!

VS2005 Web Application Project v1.0 released

I've blogged about this before here and here, but it's definitely good news that Scott Guthrie has announced that
VS 2005 Web Application Project V1.0 has been released.

Having now worked extensively with the "Whidbey" web project model, I'm glad that this alternative is available and supported. I have a feeling that the Web Application Project model is actually going to be the more used - at least amongst the professional development community - as it provides much more control over the structure of your project.

As always, this is my 2p and your mileage may vary.

Closing the circle... Finding that missing Linq

I've been looking at Linq recently in the context of using it in anger to provide in-memory filtering of List<thing> instances.

My problem was that I had an existing class library project that I needed to "Linq enable", and just adding the references to System.Query et al just doesn't work.

It turns out that you need to modify the project file itself.

You can do this in any text editor easily enough, but I found this trick for doing so in VS2005.

1. Right click on the project in the solution and select "Unload Project"
2. Then right-click again and select "Edit project file" from the context menu to open the project file up in the editor. This gives you all the benefits of syntax highlighting, intellisense, etc. Good stuff.
3. Make your changes to the .csproj file and save 'em
   
4. Right click on the project in the Solution Explorer and select "Reload project"
   

Now, to Linq enable a project, you need to find the line in the project file that reads

<import project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />

and replace it with the following lines

<import project="$(ProgramFiles)\LINQ Preview\Misc\Linq.targets" />
<!-- Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" / -->

Of course, your path to the Linq.targets file may be different if you've installed Linq anywhere other than the default.

Recompile your project and you'll find that all the Linq goodness is available and working within your existing project.

Web custom controls - changing the base tag

In this blog entry "A detail the Webcontrol books don't teach you", Miguel Castro tells you how to override the default behavior of a web custom control and replace the SPAN that is generated with a DIV (or any other tag!), and points out the differences needed when your control inherits from System.Web.UI.CompositeControl rather than System.Web.UI.Control.

Amazing how Googling (in this case for "web custom control render div not span") can give you exactly the answer you were after!

Fixing ATLAS Control Extenders

ATLAS is a really nice piece of technology, allowing you to AJAX enable an ASP.Net page. The recently released ATLAS Control Toolkit provides a suite of ATLAS controls that are useful out of the box, and provide a good set of samples for developing your own.

Of course, the problem with using any third party control is that you may have trouble when the control doesn't work in quite the way you expect.

I've been having a problem with the Popup Control Extender recently. It's a control to let you use one control on an ASP.Net page to toggle the visibility of another - and being part of the ATLAS Control Toolkit, it's fully ATLAS enabled and so renders the behavior on the client.

The problem was that the designers of the toolkit didn't consider the case when the extender was used in a composite control that was repeated on a page. The toolkit renders markup on the page for behavioral properties exposed from the extender, but wasn't catering for when the extender was itself repeated as part of a composite control.

Fortunately, the source code for the Popup Control Extender comes with the ATLAS Control Toolkit itself, so I was able to fix the fault myself - score one for open / shared source!

I posted the full fix in the ASP.NET Forums - hopefully others will find it useful. I'm just made up to be able to contribute something back for a change!

Getting at HttpServerUtility

Here's the problem - you want to HTML encode some content in a class library that supports your ASP.Net application... You could write the routine to HTML encode a string yourself, or you could re-factor your code to do the encoding in the page code-behind like this:

public partial class DemoPage : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
LabelControl.Text =
Server.HtmlEncode( LibraryClassInstance.Content );
}

// rest of the implementation goes here
}

But what if you're abstracting things so that a library object has to be able to render itself as HTML?

The problem is all about getting at the HtmlEncode method if you've not got a Server object handy. The Server object is actually a singleton instance of the HttpServerUtility class exposed by the ASP.Net environment from the HttpContext in which the page is running.

HOWEVER, the HttpContext class exposes a static method to return the current context instance, including the associated HttpServerUtility instance, so all you have to do in the library is the following

namespace demo
{
class LibraryClass
{
public string GetHtmlSafeContent()
{
return HttpContext.Current.Server.HtmlEncode(this.Content);
}

// remainder of the implementation goes here
}
}

Voila - HTML (and URL) encoding and de-coding at your fingertips.

Design-time goodness: ImageUrls

When you're developing web server controls, how often do you expose a Url or an ImageUrl property? Chances are that it's one of those tasks that happens 9 times out of 10, as adding image support to an existing or composite control is that common a task.

In this forum post, Steven Cheng from MS support gives a good code-snippet for a property that has the default ImageUrl designer applied to it. Unfortunately, he neglects to point out the assembly references needed to get it to work.

To use the standard designers requires you to reference the System.Design.dll assembly in your control library, and then to add the using statements highlighted in the sample below

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Design;
using System.Drawing.Design;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.Design;

namespace DemoControls
{
[DefaultProperty("Caption")]
[ToolboxData("<{0}:CoolButton runat=server>")]
public class CoolButton : ImageButton
{
[Bindable(true)]
[Category("Appearance")]
[DefaultValue("")]
[Localizable(true)]
[Editor("System.Web.UI.Design.ImageUrlEditor, System.Design,Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a",typeof(UITypeEditor))]
public string RolloverImageUrl
{
get
{
String s = (String)ViewState["RolloverImageUrl"];
return ((s == null) ? String.Empty : s);
}
set
{
ViewState["RolloverImageUrl"] = value;
}
}

// rest of the implementation goes here...
}

Adding this kind of design-time support is a snip, and makes those simple extended controls much more usable.

Source Code for the Built-in ASP.NET 2.0 Providers Now Available for Download

In his blog, ScottGu today announced:

Today we released the source code for the built-in ASP.NET 2.0 Membership, Role Management, Site Navigation, Session State, Profile, Web Events, and Web Part Personalization providers

This is a great thing - not only is Microsoft being much more helpful by providing sample code to let us develop (in this case) pluggable providers, but rather than releasing ????? code which just demonstrates the concepts, they're releasing the production code that we're already using.

The ASP.Net developer centre also great documentation on the Provider design pattern/model, and the individual provider types used by ASP.Net 2.0.

Finally, they've also released this under the Microsoft Permissive License (Ms-PL) - a license that allows and encourages the development of derivative works.

I for one can see myself using all of these types of providers at some point or other in my current project, so these samples are going to make my life much easier. Good stuff.

VS2005 Web Application Projects hits RC1

I've blogged about this VS2005 add-in before, as it provides a much better migration experience for complex web applications.

But today Robert Shelton posted that the add-in has now reached RC1. This is a good thing, as a (nearly) production ready toolkit for migrating "old" ASP.Net 1.1 web applications is sorely needed.

You can read his blog post here and get the download here.

Moving a development team forward - "scrimages"

In this blog article, David L details how he implemented a "Developer training regime" at a client in order to move the team's .Net development skills forward and prepare them to migrate to ASP.Net 2.0.

Apart from the (slightly dubious) American Football metaphor, the concept is remarkably similar to the Developer-to-Developer training that Angel Solutions and Mandogroup have already implemented, and that I intend on implementing here at In4Tek.

The article makes a good read, however, and is a timely reminder about the value of your developer's skill-sets and keeping them up to date, but also serves as a reminder that the training should perhaps have rather more focus on the end goal (in this case of migration) than be open-ended as the Mandogroup training has been thus far.

Check the article out here:

http://blogs.msdn.com/davidlem/archive/2006/04/13/575344.aspx

Columbus would have been proud - extending the ATLAS

The ATLAS group have been busy - today they announced the release of the ATLAS Control Toolkit. From the introduction.

The 'Atlas' Control Toolkit is a collection of samples and components that makes it easier then ever to build and consume rich client-side “Atlas” controls and extenders. The toolkit provides both ready to go samples and a powerful SDK to simplify the creation and re-use of your own custom controls and extenders.

As always, the best way to evaluate at a toolkit like this is to look at the samples provided, and the ATLAS toolkit doesn't disappoint, with 9 new controls and extenders that cover some of the most common AJAX features you'd need to make a site provide a rich and dynamic experience.

My particular favorites include the PopupControl and the ReorderList - paired, these two would provide an editing experience for simple data (such as lookup table data, for example) almost as good as could be achieved with a Windows Forms client.

More later, but I can see myself using these, and the guides for developing your own ATLAS controls and extenders extensively over the next little while.

Mix-and-match Unit Testing

In this MSDN Magazine article, John Robbins presents a tiny little hack that could save a huge amount of time if you're migrating a .Net 1.1 application with NUnit tests to .Net 2.0 and Visual Studio 2005.

The hack basically involves using some compile tests to switch between NUnit and VS2005 native testing.

The code he cites was actually found in the Patterns & Practices group Composite UI block source and is remarkably simple, requiring just the following code at the head of every test class and a change from using [Test]attributes to using [TestMethod]attributes instead.

#if !NUNIT
using Microsoft.VisualStudio.TestTools.UnitTesting;
#else
using NUnit.Framework;
using TestClass = NUnit.Framework.TestFixtureAttribute;
using TestMethod = NUnit.Framework.TestAttribute;
using TestInitialize = NUnit.Framework.SetUpAttribute;
using TestCleanup = NUnit.Framework.TearDownAttribute;
#endif

Nice when you find a simple solution to an apparently intractable problem!

Developer Highway Code

My colleague Andrew Lightowler spotted this in the security section of the UK MSDN site today. The Developer Highway Code: provides a checklist of security issues that every .Net developer should keep in mind when planning and implementing a piece of software. From the introduction:

To build software that meets your security objectives, you must integrate security activities into your software development lifecycle. This handbook captures and summarises the key security engineering activities that should be an integral part of your software development processes.

At over 170 pages, it's fairly heavyweight, but well worth a read, particularly in concert with Writing Secure Code (which you can, of course, get from Amazon).

I do, however, wonder how well (or more likely badly) some of my old code would fare against these checklists!

Six pillars of AJAX application design

AJAX and ATLAS are two hot topics in the arena of web application development.

In this blog entry
, RickSP covers a talk he presented at Mix'06 on how to "Design a Better User Experience with AJAX and ATLAS", and in particular, six "lessons from the trenches". My take is that these should really be "Six pillars of AJAX application design".

The two sites he references on AJAX Design Patterns and AJAX (XMLHttpRequest) Usability are an excellent read too.

Enterprise Library 2.0 extensions.

In his blog, Tom Hollander highlights some "bloody cool Enterprise Library v2 Extensions".

Whilst mostly related to the configuration of EntLib (but including a package that integrates the config tool with VS2005), one of the comments provides a link to a Data Teir Generator for EntLib.

I think that this could be a really simple way of getting started with the EntLib - bringing it closer to the data teir functionality of Castle ActiveRecord (and its associated generator) or IdeaBlade DevForce.

YET ANOTHER toolkit to evaluate! *sigh*