ASP.NET Inline Tags

25 Jun 2008

There are all sorts of different inline tags, and I haven’t found a place that explains them all in one place, so here is the quick and dirty…

<% ... %>

The most basic inline tag, basically runs normal code:

<% if (User.IsInRole(“admin”)) { %> You can see this
<% } else { %>
You are no admin fool!
<%} %>

http://msdn2.microsoft.com/en-us/library/ms178135(vs.80).aspx

<%= ... %>

Used for small chunks of information, usually from objects and single pieces of information like a single string or int variable:

The Date is now <%= DateTime.Now.ToShortDateString() %>
The value of string1 is <%= string1 %>

http://msdn2.microsoft.com/en-us/library/6dwsdcf5(VS.71).aspx

*note: <%= is the equivalent of Response.Write() -  Courtesy of Adam from the US,thanks!

<%# .. %>

Used for Binding Expressions; such as Eval and Bind, most often found in data controls like GridView, Repeater, etc.:

<%# Eval("MeetingName") %>

http://msdn2.microsoft.com/en-us/library/ms178366.aspx

<%$ ... %>

Used for expressions, not code; often seen with DataSources:

http://msdn2.microsoft.com/en-us/library/d5bd1tad.aspx

<%@ ... %>

This is for directive syntax; basically the stuff you see at the top your your aspx pages like control registration and page declaration:

<%@ Page Language=”C#” MasterPageFile=”~/MasterPage.master” AutoEventWireup=”true” CodeFile=”Default.aspx.cs” Inherits=”_Default” Title=”Untitled Page” %> <%@ Register TagPrefix=”wp” Namespace=”CustomWebParts” %>

http://msdn2.microsoft.com/en-us/library/xz702w3e(VS.80).aspx

<%- ... -%>

This is a server side comment, stuff you don’t want anyone without code access to see:

<%- sometimes end users make me angry -%>

http://msdn2.microsoft.com/en-us/library/4acf8afk.aspx

And that’s that.

Source: Naspinski