The concept of Masterpages introduced in ASP.NET “Whidbey” is really fascinating. But it seems to have one major limitation, which appears to make it quite unusable in bigger Web-Applications: There seems to be no functionality, which allows a developer to programmatically change the used Master-Page at runtime.

If you think so, you should read this article: http://msdn.microsoft.com/msdnmag/issues/04/06/ASPNET20MasterPages/default.aspx

After reading this, you'll be able to change the MasterPage at runtime using the new PreInit-Event:

protected override void OnPreInit(EventArgs e)
{
  this.MasterPageFile = "OtherTemplate.master";
  base.OnPreInit(e);
}

Protected Overrides Sub OnPreInit(ByVal e As EventArgs)
   Me.MasterPageFile = "OtherTemplate.master"
   MyBase.OnPreInit(e)
End Sub

And after all, the concepts of MasterPages should work. :-)

Thanks to Scott Galloway (http://www.mostlylucid.co.uk) for his hint on this topic.