Region.GetBounds(Graphics) Method

Definition

Namespace:

System.Drawing

Assembly:

System.Drawing.Common.dll

Source:

Region.cs

Gets a RectangleF structure that represents a rectangle that bounds this Region on the drawing surface of a Graphics object.

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

Parameters

g

Graphics

The Graphics on which this Region is drawn.

Returns

RectangleF

A RectangleF structure that represents the bounding rectangle for this Region on the specified drawing surface.

Exceptions

ArgumentNullException

g is null.

Examples

The following code example is designed for use with Windows Forms, and it requires PaintEventArgs e, which is a parameter of the Paint event handler. The code performs the following actions:

• Creates a GraphicsPath and adds an ellipse to it.

• Fills the path with blue and draws it to the screen.

• Creates a region that uses the GraphicsPath.

• Gets the nonexcluded area of the region when combined with the second rectangle.

• Gets the bounding rectangle for the region and draws it to the screen in red.

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

Remarks

The current transformation of the graphics context is used to compute the region interior on the drawing surface. The bounding rectangle is not always the smallest possible bounding rectangle depending on the current transformation.