javasript实现第三位小数四舍五入

 var expensevalue = (do***ent.getElementById("edt_0_Expense").value).toString()

                point = ex***sevalue.indexOf(".");
                //***_0_Expense.value;
                last = point + 2;
                round = point + 3;
                lastvalue = parseInt(ex***sevalue.substr(last,1));
                if (parseInt(ex***sevalue.substr(round,1)) >= 5)
                    lastvalue = parseInt(ex***sevalue.substr(last,1)) + 1;
                expensevalue = ex***sevalue.substr(0, last) + la***alue.toString();

第三位小数四舍五入

或者用库函数

newexpensevalue= parseFloat(Math .round (expensevalue*100))/100;