实现一个数字转中文的方法

//阿拉伯数字转中文数字
function NoToChinese(num) {
  if (!/^\d*(\.\d*)?$/.test(num)) {
    alert("Number is wrong!");
    return "Number is wrong!";
  }
  var AA = new Array(
    "零",
    "一",
    "二",
    "三",
    "四",
    "五",
    "六",
    "七",
    "八",
    "九",
  );
  var BB = new Array("", "十", "百", "千", "万", "亿", "点", "");
  var a = ("" + num).replace(/(^0*)/g, "").split("."),
    k = 0,
    re = "";
  for (var i = a[0].length - 1; i >= 0; i--) {
    switch (k) {
      case 0:
        re = BB[7] + re;
        break;
      case 4:
        if (!new RegExp("0{4}\\d{" + (a[0].length - i - 1) + "}$").test(a[0]))
          re = BB[4] + re;
        break;
      case 8:
        re = BB[5] + re;
        BB[7] = BB[5];
        k = 0;
        break;
    }
    if (k % 4 == 2 && a[0].charAt(i + 2) != 0 && a[0].charAt(i + 1) == 0)
      re = AA[0] + re;
    if (a[0].charAt(i) != 0) re = AA[a[0].charAt(i)] + BB[k % 4] + re;
    k++;
  }
  if (a.length > 1) {
    //加上小数部分(如果有小数部分)
    re += BB[6];
    for (var i = 0; i < a[1].length; i++) re += AA[a[1].charAt(i)];
  }
  return re;
}