語言

Region.MakeEmpty 方法

定義

初始 Region 化為空的內部。

public:
 void MakeEmpty();
public void MakeEmpty();
member this.MakeEmpty : unit -> unit
Public Sub MakeEmpty ()

範例

以下程式碼範例示範如何使用 Region 建構子與 MakeEmpty 方法。 此範例設計用於 Windows 表單。 建立一個表單,然後把以下程式碼貼上去。 以該表單的事件處理方法呼叫該FillEmptyRegion方法,並通過為 Painte。PaintEventArgs

private:
   void FillEmptyRegion( PaintEventArgs^ e )
   {
      // Create a region from a rectangle.
      Rectangle originalRectangle = Rectangle(40,40,40,50);
      System::Drawing::Region^ smallRegion = gcnew System::Drawing::Region( originalRectangle );

      // Call MakeEmpty.
      smallRegion->MakeEmpty();

      // Fill the region in red and draw the original rectangle
      // in black. Note there is nothing filled in.
      e->Graphics->FillRegion( Brushes::Red, smallRegion );
      e->Graphics->DrawRectangle( Pens::Black, originalRectangle );
   }
private void FillEmptyRegion(PaintEventArgs e)
{

    // Create a region from a rectangle.
    Rectangle originalRectangle = new Rectangle(40, 40, 40, 50);
    Region smallRegion = new Region(originalRectangle);

    // Call MakeEmpty.
    smallRegion.MakeEmpty();

    // Fill the region in red and draw the original rectangle
    // in black. Note there is nothing filled in.
    e.Graphics.FillRegion(Brushes.Red, smallRegion);
    e.Graphics.DrawRectangle(Pens.Black, originalRectangle);
}
Private Sub FillEmptyRegion(ByVal e As PaintEventArgs)

    ' Create a region from a rectangle.
    Dim originalRectangle As New Rectangle(40, 40, 40, 50)
    Dim smallRegion As New Region(originalRectangle)

    ' Call MakeEmpty.
    smallRegion.MakeEmpty()

    ' Fill the region in red and draw the original rectangle
    ' in black. Note there is nothing filled in.
    e.Graphics.FillRegion(Brushes.Red, smallRegion)
    e.Graphics.DrawRectangle(Pens.Black, originalRectangle)

End Sub

適用於