Help for right syntax in .net for defining variables in web pages

[devp10]

Help for right syntax in .net for defining variables in web pages

I am trying to create a website in asp.net with multiple navigations links. A sample of the same in .asp is:

Define a variable on the homepage:
<%
Dim varSection
varSection = Request.Form("varSection")
If varSection = "" Then
varSection = "Home"
End If%>

And then call frm an include file as:

<% If varSection = "Home" Then %>
Display this content
<% End If %>

<% If varSection = "Abt" Then %>
Display this content
<% End If %>

Likewise, I seek help with the right syntax in asp.net as above.

Currently my homepage in asp.net just has the following code:
<%@ Register TagPrefix="MY" TagName="top" src="includes/top.ascx"%>
<%@ Register TagPrefix="Page" TagName="left" src="includes/left.ascx"%>
<%@ Register TagPrefix="Header" TagName="right" src="includes/right.ascx"%>
<%@ Register TagPrefix="Hdr" TagName="bottom" src="includes/bottom.ascx"%>