JS实现数字格式千分位相互转换方法

 /**
   * 数字格式转换成千分位
   *@param{Object}num
   */
  function commafy(num) {
    if ((num + "").trim() == "") {
      return "";
    }
    if (isNaN(num)) {
      return "";
    }
    num = num + "";
    if (/^.*\..*$/.test(num)) {
      varpointIndex = num.lastIndexOf(".");
      varintPart = num.substring(0, pointIndex);
      varpointPart = num.substring(pointIndex + 1, num.length);
      intPart = intPart + "";
      var re = /(-?\d+)(\d{3})/;
      while (re.test(intPart)) {
        intPart = intPart.replace(re, "$1,$2");
      }
      num = intPart + "." + pointPart;
    } else {
      num = num + "";
      var re = /(-?\d+)(\d{3})/;
      while (re.test(num)) {
        num = num.replace(re, "$1,$2");
      }
    }
    return num;
  }

 

/**
   * 去除千分位
   *@param{Object}num
   */

  function delcommafy(num) {
    if ((num + "").trim() == "") {
      return "";
    }
    num = num.replace(/,/gi, "");
    returnnum;
  }