Programming .NET Windows Applications

ListControls

In addition to the TreeView and ListView controls described in the previous chapter, the .NET Framework provides three other controls that display lists of items: the ListBox, the CheckedListBox, and the ComboBox. All derive from the ListControl base class shown in Figure 15-1. The ListControl class is abstract (MustInherit in VB.NET); it cannot be instantiated itself, but concrete classes derived from it can be instantiated.

The ListControl class provides much (although not all, as you will see) of the common functionality of these three controls. Table 15-1 lists the five native properties of the ListControl class that are inherited by derived classes. These properties include the DataSource property and several properties useful to a single-selection list. Table 15-2 lists properties that are not actually members of the ListControl class, but are members of all three derived classes. They include properties used to define the appearance of the control and properties related to the controls' Items collection, described next. Table 15-3 lists commonly used methods of the ListControl class.

Table 15-1. ListControl properties

Property	Value type	Description
DataSource	Object	Read/write. Specifies the data source for the list control.
DisplayMember	String	Read/write. Specifies the property of the data source displayed by the list control.
SelectedValue	Object	Read/write. Contains the value of the currently selected item specified by the ValueMember property. ...