Using the RadioButtonList Class

The RadioButtonList control lets you display a list of radio buttons. Here is the inheritance hierarchy of this class:

Object
   Control
      WebControl
         ListControl
            RadioButtonList

To determine which item is selected in a radio button control, you can test the SelectedItem property of the list. You also can determine the index of the selected item with the SelectedIndex property. Each item in the radio button list's Items collection (inherited from the ListControl class) is an object of the ListItem class (see "Using the ListItem Class" in this chapter), and you can use the ListItem class's Value, Text, and Selected properties to work with the radio buttons in the list like this: RadioButtonList1.Items(5).Selected.

You can customize how the list is displayed using the RepeatLayout and RepeatDirection properties. If RepeatLayout is set to RepeatLayout.Table (which is the default), the list is drawn in an HTML table. If it is set to RepeatLayout.Flow, on the other hand, the list is drawn without a table. And by default, RepeatDirection is set to RepeatDirection.Vertical. Setting this property to RepeatDirection.Horizontal draws the list horizontally.

You can find the notable public properties of RadioButtonList objects in Table 16.13, the notable methods in Table 16.14, and the notable public events in Table 16.15. Note that as with other Web server controls, I am not listing the notable properties, methods, and events this class inherits from the Control and WebControl classes; you can find them in Tables 15.1 to 15.5 in Chapter 15. This class also inherits from the ListControl class you can find the notable public properties of ListControl objects in Table 16.4, and their notable public events in Table 16.5. (This class has no non-inherited methods.)