Region.GetBounds(Graphics) 方法

定义

命名空间:

System.Drawing

程序集:

System.Drawing.Common.dll

包:

System.Drawing.Common v9.0.0-rc.2.24474.1

Source:

Region.cs

获取一个 RectangleF 结构，该结构表示在 Graphics 对象的绘图图面上绑定此 Region 的矩形。

public:
 System::Drawing::RectangleF GetBounds(System::Drawing::Graphics ^ g);

public System.Drawing.RectangleF GetBounds (System.Drawing.Graphics g);

member this.GetBounds : System.Drawing.Graphics -> System.Drawing.RectangleF

Public Function GetBounds (g As Graphics) As RectangleF

参数

g

Graphics

绘制此 Region 的 Graphics。

返回

RectangleF

表示指定绘图图面上此 Region 的边界矩形的 RectangleF 结构。

例外

ArgumentNullException

g null。

示例

下面的代码示例设计用于 Windows 窗体，它需要 PaintEventArgse，这是 Paint 事件处理程序的参数。 该代码执行以下操作：

• 创建 GraphicsPath 并为其添加省略号。

• 用蓝色填充路径，并将其绘制到屏幕。

• 创建使用 GraphicsPath的区域。

• 当与第二个矩形组合时，获取区域的非excluded 区域。

• 获取区域的边界矩形，并将其绘制到红色屏幕。

public:
   void GetBoundsExample( PaintEventArgs^ e )
   {
      // Create a GraphicsPath and add an ellipse to it.
      GraphicsPath^ myPath = gcnew GraphicsPath;
      Rectangle ellipseRect = Rectangle(20,20,100,100);
      myPath->AddEllipse( ellipseRect );

      // Fill the path with blue and draw it to the screen.
      SolidBrush^ myBrush = gcnew SolidBrush( Color::Blue );
      e->Graphics->FillPath( myBrush, myPath );

      // Create a region using the GraphicsPath.
      System::Drawing::Region^ myRegion = gcnew System::Drawing::Region( myPath );

      // Get the bounding rectangle for myRegion and draw it to the
      // screen in Red.
      RectangleF boundsRect = myRegion->GetBounds( e->Graphics );
      e->Graphics->DrawRectangle( Pens::Red, Rectangle::Round( boundsRect ) );
   }

public void GetBoundsExample(PaintEventArgs e)
{
             
    // Create a GraphicsPath and add an ellipse to it.
    GraphicsPath myPath = new GraphicsPath();
    Rectangle ellipseRect = new Rectangle(20, 20, 100, 100);
    myPath.AddEllipse(ellipseRect);
             
    // Fill the path with blue and draw it to the screen.
    SolidBrush myBrush = new SolidBrush(Color.Blue);
    e.Graphics.FillPath(myBrush, myPath);
             
    // Create a region using the GraphicsPath.
    Region myRegion = new Region(myPath);
             
    // Get the bounding rectangle for myRegion and draw it to the
             
    // screen in Red.
    RectangleF boundsRect = myRegion.GetBounds(e.Graphics);
    e.Graphics.DrawRectangle(Pens.Red, Rectangle.Round(boundsRect));
}

Public Sub GetBoundsExample(ByVal e As PaintEventArgs)

    ' Create a GraphicsPath and add an ellipse to it.
    Dim myPath As New GraphicsPath
    Dim ellipseRect As New Rectangle(20, 20, 100, 100)
    myPath.AddEllipse(ellipseRect)

    ' Fill the path with blue and draw it to the screen.
    Dim myBrush As New SolidBrush(Color.Blue)
    e.Graphics.FillPath(myBrush, myPath)

    ' Create a region using the GraphicsPath.
    Dim myRegion As New [Region](myPath)

    ' Get the bounding rectangle for myRegion and draw it to the
    ' screen in Red.
    Dim boundsRect As RectangleF = myRegion.GetBounds(e.Graphics)
    e.Graphics.DrawRectangle(Pens.Red, Rectangle.Round(boundsRect))
End Sub

注解

图形上下文的当前转换用于计算绘图图面上的区域内部。 边界矩形并不总是尽可能小的边界矩形，具体取决于当前转换。