Region.Dispose 方法

定义

释放此 Region 使用的所有资源。

public:
 virtual void Dispose();
public void Dispose ();
abstract member Dispose : unit -> unit
override this.Dispose : unit -> unit
Public Sub Dispose ()

实现

示例

下面的代码示例演示构造 Region 函数和 ExcludeDispose 方法。

此示例旨在与 Windows 窗体 一起使用。 将代码粘贴到窗体中,并在处理窗体的 Paint 事件时调用 FillRegionExcludingPath 方法,作为 ePaintEventArgs传递。

private:
   void FillRegionExcludingPath( PaintEventArgs^ e )
   {
      // Create the region using a rectangle.
      System::Drawing::Region^ myRegion = gcnew System::Drawing::Region( Rectangle(20,20,100,100) );

      // Create the GraphicsPath.
      System::Drawing::Drawing2D::GraphicsPath^ path = gcnew System::Drawing::Drawing2D::GraphicsPath;

      // Add a circle to the graphics path.
      path->AddEllipse( 50, 50, 25, 25 );

      // Exclude the circle from the region.
      myRegion->Exclude( path );

      // Retrieve a Graphics object from the form.
      Graphics^ formGraphics = e->Graphics;

      // Fill the region in blue.
      formGraphics->FillRegion( Brushes::Blue, myRegion );

      // Dispose of the path and region objects.
      delete path;
      delete myRegion;
   }
private void FillRegionExcludingPath(PaintEventArgs e)
{

    // Create the region using a rectangle.
    Region myRegion = new Region(new Rectangle(20, 20, 100, 100));

    // Create the GraphicsPath.
    System.Drawing.Drawing2D.GraphicsPath path = 
        new System.Drawing.Drawing2D.GraphicsPath();

    // Add a circle to the graphics path.
    path.AddEllipse(50, 50, 25, 25);

    // Exclude the circle from the region.
    myRegion.Exclude(path);

    // Retrieve a Graphics object from the form.
    Graphics formGraphics = e.Graphics;

    // Fill the region in blue.
    formGraphics.FillRegion(Brushes.Blue, myRegion);

    // Dispose of the path and region objects.
    path.Dispose();
    myRegion.Dispose();
}
Private Sub FillRegionExcludingPath(ByVal e As PaintEventArgs)

    ' Create the region using a rectangle.
    Dim myRegion As New Region(New Rectangle(20, 20, 100, 100))

    ' Create the GraphicsPath.
    Dim path As New System.Drawing.Drawing2D.GraphicsPath

    ' Add a circle to the graphics path.
    path.AddEllipse(50, 50, 25, 25)

    ' Exclude the circle from the region.
    myRegion.Exclude(path)

    ' Retrieve a Graphics object from the form.
    Dim formGraphics As Graphics = e.Graphics

    ' Fill the region in blue.
    formGraphics.FillRegion(Brushes.Blue, myRegion)

    ' Dispose of the path and region objects.
    path.Dispose()
    myRegion.Dispose()

End Sub

注解

调用 Dispose 允许重新分配用于 Region 其他目的的资源。

在完成使用 Dispose 后,应调用 RegionDispose 方法使 Region 处于不可用状态。 调用 Dispose后,必须释放对 Region 的所有引用,以便垃圾回收器可以回收 占用的内存 Region 。 有关详细信息,请参阅清理非托管资源和实现 Dispose 方法

注意

每次释放对 Dispose 的最后一个引用前,均应调用 Region。 否则,在垃圾回收器调用 Region 对象的 Finalize 方法之前,该对象正在使用的资源不会被释放。

适用于