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CheckBox Constructor

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Initializes a new instance of the CheckBox class.

public:
 CheckBox();
public CheckBox ();
Public Sub New ()

Examples

Note

The following code sample uses the single-file code model and may not work correctly if copied directly into a code-behind file. This code sample must be copied into an empty text file that has an .aspx extension. For more information on the Web Forms code model, see ASP.NET Web Forms Page Code Model.


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

<!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 runat="server">
    <title> CheckBox Constructor Example </title>
<script runat="server">

      void Page_Load(Object sender, EventArgs e)
      {

         // Create new CheckBox control.
         CheckBox NewCheckBox = new CheckBox();
         NewCheckBox.ID="FeatureCheckBox";
         NewCheckBox.Text="Enable feature";
         NewCheckBox.AutoPostBack = true;

         // Register the event-handling method for the CheckedChanged event. 
         NewCheckBox.CheckedChanged += new EventHandler(this.Check_Change);

         // Add the control to the Controls collection of the
         // PlaceHolder control. 
         Place.Controls.Clear();
         Place.Controls.Add(NewCheckBox);

      }

      void Check_Change(Object sender, EventArgs e)
      {

         // Retrieve the CheckBox control from the PlaceHolder control.
         CheckBox check = (CheckBox)Place.FindControl("FeatureCheckBox");

         // Display the appropriate message based on the state of the
         // CheckBox control. 
         if(check.Checked)
         {
            Message.Text = "Feature enabled.";
         }
         else
         {
            Message.Text = "Feature disabled.";
         }

      }

   </script>

</head>

<body>

   <form id="form1" runat="server">

      <h3> CheckBox Constructor Example </h3>

      Click the check box.

      <br /><br />

      <asp:Placeholder id="Place" 
           runat="server"/>

      <br /><br />

      <asp:Label id="Message" 
           runat="server"/>

   </form>

</body>

</html>


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

<!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 runat="server">
    <title> CheckBox Constructor Example </title>
<script runat="server">

      Sub Page_Load(sender As Object, e As EventArgs)

         ' Create new CheckBox control.
         Dim NewCheckBox As CheckBox = New CheckBox()
         NewCheckBox.ID="FeatureCheckBox"
         NewCheckBox.Text="Enable feature"
         NewCheckBox.AutoPostBack = True

         ' Register the event handling method for the CheckedChanged event. 
         AddHandler NewCheckBox.CheckedChanged, AddressOf Check_Change

         ' Add the control to the Controls collection of the
         ' PlaceHolder control. 
         Place.Controls.Clear()
         Place.Controls.Add(NewCheckBox)

      End Sub

      Sub Check_Change(sender As Object, e As EventArgs)

         ' Retrieve the CheckBox control from the PlaceHolder control.
         Dim check As CheckBox = _
            CType(Place.FindControl("FeatureCheckBox"), CheckBox)

         ' Display the appropriate message based on the state of the
         ' CheckBox control. 
         If check.Checked Then
         
            Message.Text = "Feature enabled."
     
         Else
         
            Message.Text = "Feature disabled."
         
         End If


      End Sub

   </script>

</head>

<body>

   <form id="form1" runat="server">

      <h3> CheckBox Constructor Example </h3>

      Click the check box.

      <br /><br />

      <asp:Placeholder id="Place" 
           runat="server"/>

      <br /><br />

      <asp:Label id="Message" 
           runat="server"/>

   </form>

</body>

</html>

Remarks

Use this constructor to create and initialize a new instance of the CheckBox class.

Applies to