MasterType in ASP.NET 2.0
Here is something nice that comes from the new compilation model in ASP.NET 2.0. Let’s say you add a custom property to a master page code-behind file like so:
Partial Class otcMaster
Inherits System.Web.UI.MasterPage
Public Property FooterText() As String
Get
Return Footer.Text
End Get
Set(ByVal value As String)
Footer.Text = value
End Set
End Property
End ClassYou can get to the master page for a web form using the inherited Master property, which returns a MasterPage reference. To get to a property defined in otcMasterPage though, you might think you need to use a cast.
CType(Master, otcMaster).FooterText ="foo"
Casting to a derived type is just a part of life when using frameworks and statically typed languages, but there is a better way. Use the @ MasterType directive in the ASPX.
<%@ MasterType VirtualPath="~/otc.master" %>
Now when ASP.NET codegens the page, it puts the following inside a partial class definition. Notice the Shadows keyword (that would be the new keyword in semicolon land [yeah, I’m experimenting with alternative languages]).
Public Shadows ReadOnly Property Master() As otc
Get
Return CType(MyBase.Master,otcMaster)
End Get
End PropertyThe result is a strongly typed Master Page. We don’t need a cast, we can go right to the Master.FooterText property. Another way to do this is to specify a TypeName in the @MasterType directive.