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

Public Sub Exclude_RectF_Example(ByVal e As PaintEventArgs)

    ' Create the first rectangle and draw it to the screen in black.
    Dim regionRect As New Rectangle(20, 20, 100, 100)
    e.Graphics.DrawRectangle(Pens.Black, regionRect)

    ' create the second rectangle and draw it to the screen in red.
    Dim complementRect As New RectangleF(90, 30, 100, 100)
    e.Graphics.DrawRectangle(Pens.Red, _
    Rectangle.Round(complementRect))

    ' Create a region using the first rectangle.
    Dim myRegion As New [Region](regionRect)

    ' Get the nonexcluded area of myRegion when combined with
    ' complementRect.
    myRegion.Exclude(complementRect)

    ' Fill the nonexcluded area of myRegion with blue.
    Dim myBrush As New SolidBrush(Color.Blue)
    e.Graphics.FillRegion(myBrush, myRegion)
End Sub

' 导入命名空间
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Windows.Forms

public class ClipRegionExclude
   public Shared Sub Main
        Application.Run(New Form1)
   End Sub
End class

public class Form1
  Inherits System.Windows.Forms.Form

  Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
        Dim g As Graphics = Me.CreateGraphics()
        g.Clear(Me.BackColor)
        Dim pen As New Pen(Color.Red, 5)
        Dim brush As New SolidBrush(Color.Red)
        Dim rect1 As New Rectangle(50, 0, 50, 150)
        Dim rect2 As New Rectangle(0, 50, 150, 50)
        Dim [region] As New [Region](rect1)
        [region].Exclude(rect2)
        g.FillRegion(brush, [region])
        g.Dispose()

  End Sub

  Public Sub New()
   
    MyBase.New()
    Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
    Me.ClientSize = New System.Drawing.Size(292, 273)
    Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen

  End Sub

End Class