{
The following code loads a bitmap from a file and assigns it to the Brush of the Canvas of Form1:
} 
var
  Bitmap: TBitmap;
begin
  Bitmap := TBitmap.Create;
  try
    Bitmap.LoadFromFile('MyBitmap.bmppng');
    Form1.Canvas.Brush.Bitmap := Bitmap;
    Form1.Canvas.FillRect(Rect(0,0,100,100));
  finally
    Form1.Canvas.Brush.Bitmap := nil;
    Bitmap.Free;
  end;
end; 
