Control.Region Property

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Source:

Control.cs

Gets or sets the window region associated with the control.

public:
 property System::Drawing::Region ^ Region { System::Drawing::Region ^ get(); void set(System::Drawing::Region ^ value); };

[System.ComponentModel.Browsable(false)]
public System.Drawing.Region? Region { get; set; }

[<System.ComponentModel.Browsable(false)>]
member this.Region : System.Drawing.Region with get, set

Public Property Region As Region

Property Value

Region

The window Region associated with the control.

Attributes

BrowsableAttribute

Examples

The following code example demonstrates how to use the Region property by creating a round button. To run the example, paste the following code in a form containing a button called roundButton. This example requires that the Paint event is connected to the event handler defined in the example.

private:
   // This method will change the square button to a circular button by 
   // creating a new circle-shaped GraphicsPath object and setting it 
   // to the RoundButton objects region.
   void roundButton_Paint( Object^ sender,
      System::Windows::Forms::PaintEventArgs^ e )
   {
      System::Drawing::Drawing2D::GraphicsPath^ buttonPath =
         gcnew System::Drawing::Drawing2D::GraphicsPath;
      
      // Set a new rectangle to the same size as the button's 
      // ClientRectangle property.
      System::Drawing::Rectangle newRectangle = roundButton->ClientRectangle;
      
      // Decrease the size of the rectangle.
      newRectangle.Inflate(  -10, -10 );
      
      // Draw the button's border.
      e->Graphics->DrawEllipse( System::Drawing::Pens::Black, newRectangle );
      
      // Increase the size of the rectangle to include the border.
      newRectangle.Inflate( 1, 1 );
      
      // Create a circle within the new rectangle.
      buttonPath->AddEllipse( newRectangle );
      
      // Set the button's Region property to the newly created 
      // circle region.
      roundButton->Region = gcnew System::Drawing::Region( buttonPath );
   }

// This method will change the square button to a circular button by 
// creating a new circle-shaped GraphicsPath object and setting it 
// to the RoundButton objects region.
private void roundButton_Paint(object sender, 
    System.Windows.Forms.PaintEventArgs e)
{

    System.Drawing.Drawing2D.GraphicsPath buttonPath = 
        new System.Drawing.Drawing2D.GraphicsPath();

    // Set a new rectangle to the same size as the button's 
    // ClientRectangle property.
    System.Drawing.Rectangle newRectangle = roundButton.ClientRectangle;

    // Decrease the size of the rectangle.
    newRectangle.Inflate(-10, -10);
    
    // Draw the button's border.
    e.Graphics.DrawEllipse(System.Drawing.Pens.Black, newRectangle);

    // Increase the size of the rectangle to include the border.
    newRectangle.Inflate( 1,  1);

    // Create a circle within the new rectangle.
    buttonPath.AddEllipse(newRectangle);
            
    // Set the button's Region property to the newly created 
    // circle region.
    roundButton.Region = new System.Drawing.Region(buttonPath);
}

' This method will change the square button to a circular button by 
' creating a new circle-shaped GraphicsPath object and setting it 
' to the RoundButton objects region.
Private Sub roundButton_Paint(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.PaintEventArgs) Handles roundButton.Paint

    Dim buttonPath As New System.Drawing.Drawing2D.GraphicsPath

    ' Set a new rectangle to the same size as the button's 
    ' ClientRectangle property.
    Dim newRectangle As Rectangle = roundButton.ClientRectangle

    ' Decrease the size of the rectangle.
    newRectangle.Inflate(-10, -10)

    ' Draw the button's border.
    'e.Graphics.DrawEllipse(System.Drawing.Pens.Black, newRectangle)

    'Increase the size of the rectangle to include the border.
    newRectangle.Inflate(1, 1)

    ' Create a circle within the new rectangle.
    buttonPath.AddEllipse(newRectangle)
    e.Graphics.DrawPath(Pens.Black, buttonPath)
    ' Set the button's Region property to the newly created 
    ' circle region.
    roundButton.Region = New System.Drawing.Region(buttonPath)

End Sub

Remarks

The window region is a collection of pixels within the window where the operating system permits drawing. The operating system does not display any portion of a window that lies outside of the window region. The coordinates of a control's region are relative to the upper-left corner of the control, not the client area of the control.

Note

The collection of pixels contained with the region can be noncontiguous.

See also

• ClientRectangle
• Bounds