The Code-Behind File

You can interweave content such as HTML, text, server controls, and program code in a single file, as was done with traditional ASP. This is known, cleverly, as the single-file model.

To see an example of the single-file model, look at CodeSingleFile.aspx, listed in Example 6-1.

Example 6-1. CodeSingleFile.aspx

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
   protected void btnHello_Click(object sender, EventArgs e)
   {
      lblMessage.Text = "Hello. The time is " +
         DateTime.Now.ToLongTimeString();
   }
</script>

<html>
<head runat="server">
   <title>Single File Demo</title>
</head>
<body>
   <form id="form1" runat="server">
   <div>
      <h1>Code-Beside</h1>
      <asp:Button ID="btnHello" runat="server"
         Text="Hello" OnClick="btnHello_Click" />
      <br />
      <asp:Label ID="lblMessage" runat="server" />
   </div>
   </form>
</body>
</html>

If you place this file in a folder on your machine (such as c:\websites), create a virtual directory in Internet Information Services (IIS) pointing to that folder (named, for example, Websites), and then enter in your browser the URL http://localhost/websites/CodeSingleFile.aspx, the page will appear, containing a button that will display a text string every time it is clicked.

Tip

IntelliSense is available as you write code blocks, HTML, and server controls. New in VS2008, IntelliSense is also available for Cascading Style Sheets (CSS) and JavaScript. ...

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