/**
    * 將數(shù)值四舍五入后格式化.
    *
    * @param num 數(shù)值(Number或者String)
    * @param cent 要保留的小數(shù)位(Number)
    * @param isThousand 是否需要千分位 0:不需要,1:需要(數(shù)值類型);
    * @return 格式的字符串,如'1,234,567.45'
    * @type String
    */
   function formatNumber(num,cent,isThousand) {
    num = num.toString().replace(/\$|\,/g,'');

    // 檢查傳入數(shù)值為數(shù)值類型
     if(isNaN(num))
      num = "0";

    // 獲取符號(正/負數(shù))
    sign = (num == (num = Math.abs(num)));

    num = Math.floor(num*Math.pow(10,cent)+0.50000000001); // 把指定的小數(shù)位先轉(zhuǎn)換成整數(shù).多余的小數(shù)位四舍五入
    cents = num%Math.pow(10,cent);       // 求出小數(shù)位數(shù)值
    num = Math.floor(num/Math.pow(10,cent)).toString();  // 求出整數(shù)位數(shù)值
    cents = cents.toString();        // 把小數(shù)位轉(zhuǎn)換成字符串,以便求小數(shù)位長度

    // 補足小數(shù)位到指定的位數(shù)
    while(cents.length<cent)
     cents = "0" + cents;

    if(isThousand) {
     // 對整數(shù)部分進行千分位格式化.
     for (var i = 0; i < Math.floor((num.length-(1+i))/3); i++)
      num = num.substring(0,num.length-(4*i+3))+','+ num.substring(num.length-(4*i+3));
    }

    if (cent > 0)
     return (((sign)?'':'-') + num + '.' + cents);
    else
     return (((sign)?'':'-') + num);
   }