CheckBox.Checked Property
Gets or sets a value indicating whether the CheckBox control is checked.
Assembly: System.Web (in System.Web.dll)
<BindableAttribute(True, BindingDirection.TwoWay)> <ThemeableAttribute(False)> Public Overridable Property Checked As Boolean
Property Value
Type: System.Booleantrue to indicate a checked state; otherwise, false. The default is false.
Implements
ICheckBoxControl.CheckedUse this property to determine whether the CheckBox control is checked. This property can also be used to programmatically set the state of the CheckBox control.
This property cannot be set by themes or style sheet themes. For more information, see ThemeableAttribute and ASP.NET Themes and Skins.
The following example demonstrates how to use the Checked property to determine the state of the CheckBox control.
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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="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 CheckedChanged Example</title> <script runat="server"> Sub Check_Clicked(sender As Object, e As EventArgs) ' Calculate the subtotal and display the result in currency format. ' Include tax if the check box is selected. Message.Text = CalculateTotal(checkbox1.Checked).ToString("c") End Sub Sub Page_Load(sender As Object, e As EventArgs) ' Display the subtotal without tax when the page is first loaded. If Not IsPostBack Then ' Calculate the subtotal and display the result in currency format. Message.Text = CalculateTotal(false).ToString("c") End If End Sub Function CalculateTotal(Taxable As Boolean) As Double ' Calculate the subtotal for the example. Dim Result As Double = 1.99 + 2.99 + 3.99 ' Add tax, if applicable. If(Taxable) Result += Result * 0.086 End If Return Result End Function </script> </head> <body> <form id="form1" runat="server"> <h3>CheckBox CheckedChanged Example</h3> Select whether to include tax in the subtotal. <br /><br /> <table border="1" cellpadding="5"> <tr> <th colspan="2"> Shopping cart </th> </tr> <tr> <td> Item 1 </td> <td> $1.99 </td> </tr> <tr> <td> Item 2 </td> <td> $2.99 </td> </tr> <tr> <td> Item 3 </td> <td> $3.99 </td> </tr> <tr> <td> <b>Subtotal</b> </td> <td> <asp:Label id="Message" runat="server"/> </td> </tr> <tr> <td colspan="2"> <asp:CheckBox id="checkbox1" runat="server" AutoPostBack="True" Text="Include 8.6% sales tax" TextAlign="Right" OnCheckedChanged="Check_Clicked"/> </td> </tr> </table> </form> </body> </html>
Available since 1.1
