javascript操作json

for (var i = 0; i < selectedPartList.length; i++) {

            if (selectedPartList[i].vpart_code == jsonRow.vpart_code) {

                selectedPartList.splice(i, 1);//删除一项

            }

        }

        if (quantity != "0") {

            jsonRow.vused_qty = quantity;

            selectedPartList.push(jsonRow);//添加一项

        }