Radio button allows the user to choose only one of a predefined set of options. When a user clicks on a radio button, it becomes checked, and all other radio buttons with same group become unchecked. The buttons are grouped logically if they all share the same GroupName property.
RadioButton1.Checked = True
RadioButton1.Checked = true;
Use a radio button when you want the user to choose only one option. When you want the user to choose all appropriate options, use a check box.
The following ASP.NET program gives three option button to select. When the user select any option button , the label control displays the which option button is selected.
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