IGPGraphics.GetHDC

Latest revision as of 00:30, 26 June 2013

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Description

Call this method to get a handle to the device context associated with this TGPGraphics object.

Example:

The following function has a pointer to a Graphics object as its only parameter. The function calls Graphics::GetHDC to get a handle to the device context associated with the Graphics object and then passes that device context handle to the Microsoft Windows Graphics Device Interface (GDI)Rectangle function. The call to ReleaseHDC releases the device context handle.

  AGraphics.DrawEllipse( TGPPen.Create( aclBlue ), 10, 10, 100, 50);  // GDI+

  AHdc := AGraphics.GetHDC();

    // Make GDI calls, but don't call any methods
    // on g until after the call to ReleaseHDC.
    Rectangle( AHdc, 120, 10, 220, 60);  // GDI

  AGraphics.ReleaseHDC(AHdc);

  // Ok to call methods on g again.
  AGraphics.DrawLine( TGPPen.Create( aclRed ), 240, 10, 340, 60);