Web Server Controls->ASP.NET RadioButton Control

Definition and Usage

The RadioButton control is used to display a radio button.

Tip: To create a set of radio buttons using data binding, use the RadioButtonList control!


Properties

Property Description
AutoPostBack A Boolean value that specifies whether the form should be posted immediately after the Checked property has changed or not. Default is false
Checked A Boolean value that specifies whether the radio button is checked or not
id A unique id for the control
GroupName The name of the group to which this radio button belongs
OnCheckedChanged The name of the function to be executed when the Checked property has changed
runat Specifies that the control is a server control.  Must be set to "server"
Text The text next to the radio button
TextAlign On which side of the radio button the text should appear (right or left)

Examples

Radiobutton
ASPX Source:

<script  runat="server">
Sub submit(Sender As Object, e As EventArgs)
if red.Checked then
   Label1.Text="You selected " & red.Text
elseIf green.Checked then
   Label1.Text="You selected " & green.Text
elseIf blue.Checked then
   Label1.Text="You selected " & blue.Text
end if
End Sub
</script>

<html>
<body>

<form runat="server">
Select your favorite color:
<br />
<asp:RadioButton id="red" Text="Red" Checked="True"
GroupName="colors" runat="server"/>
<br />
<asp:RadioButton id="green" Text="Green"
GroupName="colors" runat="server"/>
<br />
<asp:RadioButton id="blue" Text="Blue"
GroupName="colors" runat="server"/>
<br />
<asp:Button text="Submit" OnClick="submit" runat="server"/>
<p><asp:Label id="Label1" runat="server"/></p>
</form>

</body>
</html>

Output Result:
Select your favorite color:



  

If you click the radiobutton "Green" and then click the button "Submit",it will show:
Select your favorite color:



You selected Green 


In this example we declare three RadioButton controls, one Button control, and one Label control in an .aspx file. When the submit button is triggered, the submit subroutine is executed. The submit subroutine may respond in three ways: if the radiobutton with id="red" is selected, the server sends the message "You selected Red" to the Label control. If the radiobutton with id="green" is selected, the server sends the message "You selected Green" to the Label control. If the radiobutton with id="green" is selected, the server sends the message "You selected Blue" to the Label control.

posted on 2007-03-27 09:52  改变热爱  阅读(469)  评论(0)    收藏  举报

导航