TCanvas.Handle property

Declaration

property Handle: HDC read GetHandle write SetHandle;

Description

Handle is a HDC property that provides the device context for the drawing surface. A valid Handle is required for nearly all operations performed on the canvas.

Read access calls RequiredState, and allocates a Handle by calling CreateHandle if one does not already exist. An EInvalidGraphicOperation exception may be raised in the method if a valid handle cannot be acquired.

Setting a new value for Handle causes saved Brush, Pen, and Font handles to be reset to their default values. The AntialiasingMode for the canvas is also re-applied.

See also

• RequiredState
• CreateHandle
• DeselectHandles
• Brush
• Pen
• Font
• EInvalidGraphicOperation