Radio buttons are generally grouped together to provide a range of possible options for a single value. For example, if you want the user to select a color from a specific list of colors, you can use multiple radio buttons to present the choices. To group the radio buttons, you give each button the same name. Only the selected radio button is posted back to the server when the form is submitted.
The Html.RadioButton helper renders a simple radio button:
@Html.RadioButton("color", "red")
@Html.RadioButton("color", "blue", true)
@Html.RadioButton("color", "green")
and results in:
<input id="color" name="color" type="radio" value="red" /> <input checked="checked" id="color" name="color" type="radio" value="blue" /> <input id="color" name="color" type="radio" value="green" />
Html.RadioButton has a strongly typed counterpart, Html.RadioButtonFor. Rather than a name and a value, the strongly typed version takes an expression that identifies the object that contains the property to render, followed by a value to submit when the user selects the radio button.
@Html.RadioButtonFor(m => m.GenreId, "1") Rock @Html.RadioButtonFor(m => m.GenreId, "2") Jazz @Html.RadioButtonFor(m => m.GenreId, "3") Pop