Immediate Solutions: Using the <i class="emphasis">ListBox</i> Class

Immediate Solutions: Using the ListBox Class

Windows forms list boxes are based on the Control class, of course, but not directly—instead, they're based directly on the ListControl class, which also is used by other controls, such as checked list boxes. Here's the class hierarchy for the ListBox class:

Object
   MarshalByRefObject
      Component
         Control
            ListControl
               ListBox

You can find the more notable public properties of the ListBox class in Table 7.1, the more notable methods in Table 7.2, and the more notable events in Table 7.3, including those members inherited from the ListControl class. Note that as with other Windows controls, I am not listing the notable properties, methods, and events ListBox inherits from the Control class, such as the Click event—you can see all that in Tables 5.1, 5.2, and 5.3 in Chapter 5.

Table 7.1: Noteworthy public properties of *ListBox* objects.
Property	Means
ColumnWidth	Gets/sets column width; use with multicolumn list boxes.
DisplayMember	Indicates which property of objects in a list box to show. If this property if empty, the object's ToString method is used.
DrawMode	Gets/sets the drawing mode for the list box.
HorizontalExtent	Gets/sets the width a list box can scroll horizontally.
HorizontalScrollbar	Gets/sets if a horizontal scroll bar is displayed in the list box.
IntegralHeight	Gets/sets if the list box should resize so it doesn't show partial items.
ItemHeight	Gets/sets an item's height in the list box.
Items	Returns a collection of the items of the list box.
MultiColumn	Gets/sets if the list box supports multiple columns.
PreferredHeight	Returns the total height of all items in the list box.
ScrollAlwaysVisible	Gets/sets if a vertical scroll bar is always shown.
SelectedIndex	Gets/sets the index of the list box's currently selected item.
SelectedIndices	Gets a collection that contains the indices of all selected items in the list box.
SelectedItem	Gets/sets the selected item in the list box.
SelectedItems	Gets a collection containing the list box's selected items.
SelectionMode	Gets/sets the mode with which items are selected.
Sorted	Gets/sets if the items in the list box are sorted. The sort is alphabetical.
Text	Gets the text of the selected item in the list box.
TopIndex	Gets/sets the index of the first item that is visible in the list box.

Table 7.2: Noteworthy public methods of *ListBox* objects.
Methods	Means
BeginUpdate	Turns off visual updating of the list box until the EndUpdate method is called.
ClearSelected	Unselects all the items in a list box.
EndUpdate	Resumes visual updating of the list box.
FindString	Finds the first item in the list box that begins with the indicated string.
FindStringExact	Finds the first item in the list box that matches the indicated string exactly.
GetItemHeight	Returns the height of a list box item.
GetSelected	Returns True if the indicated item is selected.
IndexFromPoint	Returns the index of the item at the given coordinates.
SetSelected	Selects or deselects the indicated item in a list box.

Table 7.3: Noteworthy public events of *ListBox* objects.
Event	Means
SelectedIndexChanged	Occurs when the SelectedIndex property has changed.