xorm使用分页

func GetReceiptGoodsSuccessfulApi(form *GetReceiptGoodsSuccessfulFormApi)(receiptGoodsSuccessful ReceiptGoodsSuccessful ,err error,errResponseVo ErrResponseVo) {
	orderDo:=new(OrderDo)
//分页
	var page = form.PageNum     //页数
	if page -1 <=0{
		page = 1
	}
	var pageSize = form.PageSize    //页面大小
	has, err := drivers.Engine.Where("order_identify=? and status=9",form.OrderIdentify ).Limit(pageSize * (page) ,( page -1) * pageSize).Get(orderDo)
    if err!=nil{
		receiptGoodsSuccessful.Flag=false
		return receiptGoodsSuccessful,err,ErrResponseVo{config.DZRY_ERROE_CODE_2,"未查询到订单"}
	}
	if has {
		receiptGoodsSuccessful.Flag =true
	}
	return receiptGoodsSuccessful,nil,errResponseVo
}