TPicture 转 TBitmap

  TempBmp.width:=100;
  TempBmp.height:=100;
  TempBmp.canvas.Draw(0,0,m_PicMouseOn.Graphic);//PicMouseOnj是TPictrue类型;

TBitmap转 TPicture 

PicMouseOnj.Pictrue.Graphic:=TempBmp;//TempBmp是TBitmap类型