DrawMode DrawMode DrawMode DrawMode Enum

定义

指定如何绘制控件的元素。Specifies how the elements of a control are drawn.

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

字段

Normal Normal Normal Normal 0

控件中的所有元素都由操作系统绘制,并且元素大小都相等。All the elements in a control are drawn by the operating system and are of the same size.

OwnerDrawFixed OwnerDrawFixed OwnerDrawFixed OwnerDrawFixed 1

控件中的所有元素都是手动绘制的,并且元素大小都相等。All the elements in the control are drawn manually and are of the same size.

OwnerDrawVariable OwnerDrawVariable OwnerDrawVariable OwnerDrawVariable 2

控件中的所有元素都由手动绘制,元素大小可能不相等。All the elements in the control are drawn manually and can differ in size.

示例

下面的示例演示如何创建所有者绘制ListBox项。The following example demonstrates how to create owner-drawn ListBox items. 该代码使用DrawMode属性指定绘制的项固定大小并DrawItem要执行到每个项的绘制事件DrawItemThe code uses the DrawMode property to specify that the items drawn are fixed sized and the DrawItem event to perform the drawing of each item into the DrawItem. 该示例代码使用的属性和方法的DrawItemEventArgs类作为参数传递给要绘制项的事件处理程序。The example code uses the properties and methods of the DrawItemEventArgs class passed as a parameter to the event handler to draw the items. 此示例假定ListBox控件称为listBox1已添加到窗体,DrawItem由示例代码中定义的事件处理程序处理事件。This example assumes that a ListBox control called listBox1 has been added to a form and that the DrawItem event is handled by the event handler defined in the example code. 该示例还假定已将项添加到DrawItem包括按该顺序的"Apple"、"橙色"和"Plum"文本。The example also assumes that items have been added to the DrawItem 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

注解

此枚举如由成员DrawModeListBoxCheckedListBox,和ComboBox类。This enumeration is used by members such as DrawMode in the ListBox, CheckedListBox, and ComboBox classes.

您可以重写某些控件或某些元素的绘图。You can override the drawing of some controls or certain elements. 此枚举用于指定如果控件由操作系统绘制,或你自己的代码处理控件的绘制。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.

备注

CheckedListBox类仅支持正常; 所有者绘图模式将被忽略。The CheckedListBox class only supports Normal; owner draw modes are ignored.

有关使用详细信息DrawMode.Normal枚举,请参阅MeasureItemDrawItem事件,并ItemHeight属性。For more information about using the DrawMode.Normal enumeration, see the MeasureItem and DrawItem events, and the ItemHeight property.

适用于

另请参阅