What does the function of Register tag in .aspx

[ad]

I download the source of Portal Starter Kit form
http://www.asp.net/Default.aspx?tabindex=8&tabid=47
I find there are Register tag in many .aspx, like this HtmlModule.ascx , the
first line is

<%@ Register TagPrefix="Portal" TagName="Title"
Src="~/DesktopModuleTitle.ascx"%>

What does the function of Register tag in .aspx

 

[Juan T. Llibre]

"Register TagPrefix" initializes a User Control.

The code for the User Control is in the .ascx file,
and it's initialized in the .aspx file.

 

[ad]

I find some document in MSDN, but I still not understand about this tag.

What is the function of TagPreFix and TagName?

 

[Matt Berther]

Hello ad,

<%@ Register TagPrefix="Portal" TagName="Title" Src="~/DesktopModuleTitle.ascx"%>

TagPrefix is the prefix used for the tag and TagName is the name (after the
of the tag. Given the above example, you'd use this in an aspx file

<Portal:Title id="someId" runat="server"></Portal:Title>