QuickRep1.QRPrinter.Canvas.StretchDraw()函数怎么用不了啊?(100分)

用QuickRep1.QRPrinter.Canvas.StretchDraw(rect( 0, 0, round(pwidth), round(pHeight)), pagefile)总是报错,Printer.Canvas.StretchDraw(rect( 0, 0, round(pwidth), round(pHeight)), pagefile)倒是可以但用不着