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PlaceHolder Web Server Control

Reserves a location in the page control hierarchy for controls that are added programmatically.

<asp:PlaceHolder id="PlaceHolder1" 
     runat="server"/>

Remarks

Use the PlaceHolder control as a container to store dynamically added server controls to the Web page. The PlaceHolder control does not produce any visible output and is only used as a container for other controls on the Web page. You can use the Control.Controls collection to add, insert, or remove a control from the PlaceHolder control.

Example

The following example demonstrates how to add Web server controls to the PlaceHolder control.

<%@ Page Language="VB" AutoEventWireup="True" %>

   <script runat="server">

      Sub Page_Load(Sender As Object, e As EventArgs)

         Dim myButton As HtmlButton = New HtmlButton()

         myButton.InnerText = "Button 1"
         PlaceHolder1.Controls.Add(myButton)

         myButton = New HtmlButton()
         myButton.InnerText = "Button 2"
         PlaceHolder1.Controls.Add(myButton)

         myButton = New HtmlButton()
         myButton.InnerText = "Button 3"
         PlaceHolder1.Controls.Add(myButton)

         myButton = New HtmlButton()
         myButton.InnerText = "Button 4"
         PlaceHolder1.Controls.Add(myButton)

      End Sub

   </script>

<html>
<body>
   <form runat="Server">
      <h3>PlaceHolder Example</h3>

      <asp:PlaceHolder id="PlaceHolder1" 
           runat="server"/>
   </form>
</body>
</html>
[C#]
<%@ Page Language="C#" AutoEventWireup="True" %>

   <script runat="server">

      void Page_Load(Object sender, EventArgs e)
      {
         HtmlButton myButton = new HtmlButton();

         myButton.InnerText = "Button 1";
         PlaceHolder1.Controls.Add(myButton);

         myButton = new HtmlButton();
         myButton.InnerText = "Button 2";
         PlaceHolder1.Controls.Add(myButton);

         myButton = new HtmlButton();
         myButton.InnerText = "Button 3";
         PlaceHolder1.Controls.Add(myButton);

         myButton = new HtmlButton();
         myButton.InnerText = "Button 4";
         PlaceHolder1.Controls.Add(myButton);
      }

   </script>

<html>
<body>
   <form runat="server">
      <h3>PlaceHolder Example</h3>

      <asp:PlaceHolder id="PlaceHolder1" 
           runat="server"/>
   </form>
</body>
</html>

See Also

Web Server Controls | PlaceHolder Class