Graphics::IsVisible Method (Single, Single)


Indicates whether the point specified by a pair of coordinates is contained within the visible clip region of this Graphics.

Namespace:   System.Drawing
Assembly:  System.Drawing (in System.Drawing.dll)

bool IsVisible(
	float x,
	float y


Type: System::Single

The x-coordinate of the point to test for visibility.

Type: System::Single

The y-coordinate of the point to test for visibility.

Return Value

Type: System::Boolean

true if the point defined by the x and y parameters is contained within the visible clip region of this Graphics; otherwise, false.

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

  • Creates a rectangular clipping region and sets it as the clipping region for the graphics object of the form using Replace.

  • Creates two points, one inside the clipping region and one outside.

  • Tests each of the points for visibility and draws only the visible one.

The result is one small red circle, which is within the clip region.

   void IsVisibleFloat( PaintEventArgs^ e )
      // Set clip region.
      System::Drawing::Region^ clipRegion = gcnew System::Drawing::Region( Rectangle(50,50,100,100) );
      e->Graphics->SetClip( clipRegion, CombineMode::Replace );

      // Set up coordinates of points.
      float x1 = 100.0F;
      float y1 = 100.0F;
      float x2 = 200.0F;
      float y2 = 200.0F;

      // If point is visible, fill ellipse that represents it.
      if ( e->Graphics->IsVisible( x1, y1 ) )
         e->Graphics->FillEllipse( gcnew SolidBrush( Color::Red ), x1, y1, 10.0F, 10.0F );

      if ( e->Graphics->IsVisible( x2, y2 ) )
         e->Graphics->FillEllipse( gcnew SolidBrush( Color::Blue ), x2, y2, 10.0F, 10.0F );

.NET Framework
Available since 1.1
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