More information is to follow, for now see Telerik's announcement at http://blogs.telerik.com/Blogs.aspx

I just learnt something new and cool from one of Scott Guthries blogs: the ?? null coalescing operator in C# 2.0. I never noticed it until now, and actually thought it was part of 3.0, until a kind reader corrected me... it's been around ever since the advent of nullable types in C#.

Basically, this operator works like the T-SQL ISNULL or COALESCE function. Read all about it in Scott's blog!

I recently installed the RTM version of Visual Studio 2008 (previously known as Orcas), which comes with C# 3.0 and .NET Framework 3.5. One of the coolest new things is LINQ, more on that in my next blog. The next coolest thing is the new C# 3.0 language support for lambda expressions, see the node  => part below:

XmlHelper.Visit(_rootTOCItem.ParentNode, "tocitem", 

  node => _tocItems.Add((XmlElement)node));

Where _tocItems is a List<XmlElement>  stored in the class that is calling this method.

This works because Visit accepts a delegate, and I am passing in an anonymous delegate above using the new syntax. Visit is just something I wrote that iterates over the nodes in an Xml tree. I could have used Link to Xml for that part, but this is a tree of XmlElements returned by an XmlDataProvider, and Linq to Xml operates on XElements.

public class XmlHelper

{

  public delegate void NodeVisitor(XmlNode node);

  public static void Visit( XmlNode node, string nodeNameFilter, NodeVisitor visitor )

  {

    if ( node.Name==nodeNameFilter)

      (node);

    if (node.HasChildNodes)

      foreach (XmlNode child in node.ChildNodes)

        (child, nodeNameFilter, visitor);

  }

}

I was configuring Custom Errors in the web.config of my ASP.Net 2.0 application, and set it up as follows:

<customErrors mode="remoteOnly" defaultRedirect="~/Error.aspx">
  <error statusCode="403" redirect="~/AccessDenied.aspx" />
  <error statusCode="404" redirect="~/Error404.aspx" />
</customErrors>

I had found the syntax on MSDN. To my surprise, the applicationm wouldn't start, it told me there was something wrong with the value of the mode attribute.

So I went back to MSDN and noticed I had looked at the .NET Framework 1.1 documentation. Clicking on the corresponding 2.0 documentation, I found it had changed to initial Caps:

<customErrors mode="RemoteOnly" defaultRedirect="~/Error.aspx">

Duh! I guess my chances of getting this right the first time were remote only...

I am working on a web application, and some of the client side logic uses JavaScript to get an integer value from a text box. A user logged a bug claiming that when he entered a value that had a leading 0, for instance 0556, the result was in his words "a random number".

I looked up the parseInt global function here, and lo and behold! parseInt interprets a leading 0 as denoting that an octal number follows! It also has special processing for 0x (hexadecimal). To prevent this interpretation, you can specify the radix yourself in an overload of parseInt, for instance:

parseInt( tb.value, 10 );

For base (radix) 10. 

That's all I have to say about that!

A while back I was trying to figure out how to make F1 bring up a custom help window in our web application ActiveFocus. It is easy enough to trap a keypress and open a window showing the help, but to my frustration, after popping up the new window, the built in Internet Explorer help window popped up too!

I tried various variations of cancelling the kepress event, but nothing seems to work. This is for instance how I cancel Ctrl+F (which normally pops up IEs built in Find dialog, but I wanted it to show a custom search dialog instead) :

Last week I needed to add some personalization features to our ActiveFocus application, and it seemed like the built in logic around the Profile class in ASP.Net 2.0 Personalization would do the trick. It's actually pretty neat. First, you "declare" your profile data in web.config, something like this:

<profile enabled="true">
  <providers>
    <clear/>
    <add name="AspNetSqlProfileProvider" type="System.Web.Profile.SqlProfileProvider" connectionStringName="ActiveFocus"       applicationName="/ActiveFocus"/>
  </providers>
  <properties>
    <group name="Grids">
      <add name="MainGridRows" type="System.Int16" />
      <add name="DetailGridRows" type="System.Int16" />
    </group>
    <add name="LastProject" type="System.Int32" />
  </properties>
</profile>

The Properties portion defines the profile data structure. You can use simple data types like System.Int16, nested types (like the Grids property), and your own data types. You can also declare how these types are to be serialized.

When you add a declaration like this to your project, Visual Studio 2005 generates a class for you that implements this data structure (more on how this actually needs a little help for it to work later!). The class basically wraps the HttpContext.Current.Profile object, which is of type ProfileBase. It adds accessors for the members you declared in the web.config file, and sub objects for nested types.

In runtime, the ProfileBase reads and writes it values to a column in the table aspnet_Profile. Here is what it looks like when an instance of the profile class above is written to that table:

UserId                               PropertyNames                                                          PropertyValuesString

7B07AE10-61A7-4DEE-AFF1-172BB42A5E95 Grids.DetailGridRows:S:0:1:Grids.MainGridRows:S:1:2:LastProject:S:3:1: 8202