DropDownList.CreateControlCollection Method ()

 
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Use BaseTrue

Creates a collection to store child controls.

Namespace:   System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)

protected override ControlCollection CreateControlCollection()

Return Value

Type: System.Web.UI.ControlCollection

Always returns an EmptyControlCollection.

The following code example demonstrates how to override the CreateControlCollection method in a custom server control so that it always returns a new instance of the EmptyControlCollection class for the DropDownList control. For information about using custom server controls, see Walkthrough: Developing and Using a Custom Web Server Control.

<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>Custom DropDownList - CreateControlCollection - C# Example</title>
    <script runat="server">
      private void Page_Load(object sender, System.EventArgs e)
      {
          DropDownList1.Items.Add(new ListItem("Item1", "Item1"));
          DropDownList1.Items.Add(new ListItem("Item2", "Item2"));
          DropDownList1.Items.Add(new ListItem("Item2", "Item2"));
      }
    </script>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom DropDownList - CreateControlCollection - C# Example</h3>

      <aspSample:CustomDropDownListCreateControlCollection
        id="DropDownList1"
        runat="server" />

    </form>
  </body>
</html>
using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomDropDownListCreateControlCollection : System.Web.UI.WebControls.DropDownList
    {
        protected override System.Web.UI.ControlCollection CreateControlCollection()
        {
            // Return a new empty ControlCollection
            return new System.Web.UI.EmptyControlCollection(this);
        }
    }
}

.NET Framework
Available since 1.1
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