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DrawMode Enum

Definition

Specifies how the elements of a control are drawn.

public enum class DrawMode
public enum DrawMode
type DrawMode = 
Public Enum DrawMode
Inheritance
DrawMode

Fields

Name Value Description
Normal 0

All the elements in a control are drawn by the operating system and are of the same size.

OwnerDrawFixed 1

All the elements in the control are drawn manually and are of the same size.

OwnerDrawVariable 2

All the elements in the control are drawn manually and can differ in size.

Examples

The following example demonstrates how to create owner-drawn ListBox items. The code uses the ListBox.DrawMode property to specify that the items drawn are fixed sized and the ListBox.DrawItem event to perform the drawing of each item into the ListBox. The example 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 called listBox1 has been added to a form and that the ListBox.DrawItem event is handled by the event handler defined in the example. The example also assumes that items have been added to the ListBox with the text of "Apple", "Orange", and "Plum" in that order.

private ListBox ListBox1 = new ListBox();
private void 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;
    ListBox1.DrawItem += new DrawItemEventHandler(ListBox1_DrawItem);
    Controls.Add(ListBox1);
}

private void ListBox1_DrawItem(object sender, 
    System.Windows.Forms.DrawItemEventArgs e)
{
    // Draw the background of the ListBox control for each item.
    e.DrawBackground();
    // Define the default color of the brush as black.
    Brush myBrush = Brushes.Black;

    // Determine the color of the brush to draw each item based 
    // on the index of the item to draw.
    switch (e.Index)
    {
        case 0:
            myBrush = Brushes.Red;
            break;
        case 1:
            myBrush = Brushes.Orange;
            break;
        case 2:
            myBrush = Brushes.Purple;
            break;
    }

    // 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.
    e.DrawFocusRectangle();
}
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
    Controls.Add(ListBox1)

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.
    e.DrawBackground()

    ' 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.
    e.DrawFocusRectangle()
End Sub

Remarks

This enumeration is used by members such as DrawMode in the ListBox, CheckedListBox, and ComboBox classes.

You can override the drawing of some controls or certain elements. This enumeration is used to specify if a control is drawn by the operating system or if your own code handles the drawing of the control.

Note

The CheckedListBox class only supports Normal; owner draw modes are ignored.

For more information about using the DrawMode enumeration, see the MeasureItem and DrawItem events, and the ItemHeight property.

Applies to

See also