JavaScript 把阿拉伯数字转为财务数字

替换文字

• 先把大正则匹配的内容捕获到（捕获到的结果个我们用 exec 捕获到的结果基本一致）
• 把我们捕获的内容进行替换

var str = "20151215";
var reg = /\d/g;
var ary = ["零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖"];
// 一共要捕获 8 次，我们的第二个参数 [function] 要执行 8 次
// 每一执行都把当前正则捕获的内容传递给我们的 [function]
// 每一次执行的返回值（写在 return 后面的）都相当于把当前大正则捕获的内容替换成我们返回的内容
str = str.replace(reg, function () {
    // 第一次捕获 2 ->"贰" ary[2]
    // 第二次捕获 0 ->"零" ary[0]
    //arguments[0]->每一次执行函数我们正则捕获到的内容
    console.log(arguments);
    // 第一次：arguments->["2", 0, "20151215"]  arguments[0]->"2"
    return ary[arguments[0]];//->return ary["2"] ->return "贰";
});
console.log(str);// 贰零壹伍壹贰壹伍

阿拉伯数字转为财务数字

function toChinaNumber (options) {
    options=options+"";
    options = options.replace(/^0+/, "");
    var numberAry = ["零","壹","贰","叁","肆","伍","陆","柒","捌","玖"],
            unitAry = ["","拾","佰","仟"],
            bigUnitAry = ["","万","亿"];
    var targetStr = "";
    var zeroFlag = 0;
    var i, p, nowAloneNumber;
    var quotient, modulus;
    var len=options.length;
    if(len==0){
        targetStr += "零";
    }else{
        for (i = 0; i < len; i++) {
            p = len - i - 1;
            nowAloneNumber = options.substr(i, 1);
            quotient = p / 4;// 商
            modulus = p % 4;// 余数
            if (nowAloneNumber == "0") {
                zeroFlag++;
            } else {
                if (zeroFlag > 0) {
                    targetStr += numberAry[0];
                }
                zeroFlag = 0;
                targetStr += numberAry[Number(nowAloneNumber)] + unitAry[modulus];
            }
            if (modulus == 0 && zeroFlag < 4) {
                targetStr += bigUnitAry[quotient];
                zeroFlag = 0;
            }
        }
    }
    targetStr += "元整";
    return targetStr;
}

var testNumber=35987;
var testStr="298";
console.log(toChinaNumber(testNumber));
console.log(toChinaNumber(testStr));