DrawItemEventArgs.Index Property


Gets the index value of the item that is being drawn.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

Public ReadOnly Property Index As Integer

Property Value

Type: System.Int32

The numeric value that represents the Item value of the item being drawn.

This property returns the Item value of the item being drawn in the System.Windows.Forms.Control.ControlCollection. This property can return -1 if itemswere removed from the list.

The following example demonstrates how to create owner-drawn ListBox items. The code uses the DrawMode property to specify that the items drawn are a fixed size and the DrawItem event to perform the drawing of each item into the ListBox. The example code uses the properties and methods of the DrawItemEventArgs class passed as a parameter to the event handler to draw the items. This example assumes that a ListBox control named listBox1 was added to a form and that the DrawItem event is handled by the event handler that is defined in the example code. The example also assumes that items were added to the ListBox with the text of "Apple", "Orange", and "Plum", in that order.

Private WithEvents ListBox1 As New ListBox()

Private Sub InitializeListBox() 
    ListBox1.Items.AddRange(New Object() _
        {"Red Item", "Orange Item", "Purple Item"})
    ListBox1.Location = New System.Drawing.Point(81, 69)
    ListBox1.Size = New System.Drawing.Size(120, 95)
    ListBox1.DrawMode = DrawMode.OwnerDrawFixed

End Sub

Private Sub ListBox1_DrawItem(ByVal sender As Object, _
 ByVal e As System.Windows.Forms.DrawItemEventArgs) _
 Handles ListBox1.DrawItem

    ' Draw the background of the ListBox control for each item.

    ' Define the default color of the brush as black.
    Dim myBrush As Brush = Brushes.Black

    ' Determine the color of the brush to draw each item based on   
    ' the index of the item to draw.
    Select Case e.Index
        Case 0
            myBrush = Brushes.Red
        Case 1
            myBrush = Brushes.Orange
        Case 2
            myBrush = Brushes.Purple
    End Select

    ' Draw the current item text based on the current 
    ' Font and the custom brush settings.
    e.Graphics.DrawString(ListBox1.Items(e.Index).ToString(), _
        e.Font, myBrush, e.Bounds, StringFormat.GenericDefault)

    ' If the ListBox has focus, draw a focus rectangle around  _ 
    ' the selected item.
End Sub

.NET Framework
Available since 1.1
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