JS中正负数的千位分隔符方法，利用正则表达式

Question

function cc(s){ if(/[^0-9\.]/.test(s)) return "invalid value"; s=s.replace(/^(\d*)$/,"$1."); s=(s+"00").replace(/(\d*\.\d\d)\d*/,"$1"); s=s.replace(".",","); var re=/(\d)(\d{3},)/; while(re.test(s)) s=s.replace(re,"$1,$2"); s=s.replace(/,(\d\d)$/,".$1"); return "￥" + s.replace(/^\./,"0.") }
如何修改能够使负数也可以有千位分隔符

Answer 1

使用下面给出的函数可实现千分符支持正负数：

function comma(num) {
    var source = String(num).split(".");//按小数点分成2部分
        source[0] = source[0].replace(new RegExp('(\\d)(?=(\\d{3})+$)','ig'),"$1,");//只将整数部分进行都好分割
    return source.join(".");//再将小数部分合并进来
}
comma(-123456.789);//-123,456.789

Answer 2

function cc(s) {
if (/[^0-9\.\-]/.test(s)) return "invalid value";
s = s.replace(/^(-)?(\d*)$/, "$1$2.");
s = (s + "00").replace(/(-)?(\d*\.\d\d)\d*/, "$1$2");
s = s.replace(".", ",");
var re = /(\d)(\d{3},)/;
while (re.test(s)) s = s.replace(re, "$1,$2");
s = s.replace(/,(\d\d)$/, ".$1");
return "￥" + s.replace(/^\./, "0.")
}

Answer 3

function cc(s) {
var h='';
if(s.charAt(0)=='-'){
h='-';
s=s.slice(1);
}
if (/[^0-9\.]/.test(s)) return "invalid value";
s = s.replace(/^(\d*)$/, "$1.");
s = (s + "00").replace(/(\d*\.\d\d)\d*/, "$1");
s = s.replace(".", ",");
var re = /(\d)(\d{3},)/;
while (re.test(s)) s = s.replace(re, "$1,$2");
s = s.replace(/,(\d\d)$/, ".$1");
return "￥" +h+ s.replace(/^\./, "0.")
}本回答被网友采纳