千位符封装

formatNumber: function (n) {
    var b = parseInt(n).toString();
    var len = b.length;
    if (len <= 3) {
        return b;
    }
    var r = len % 3;
    return r > 0 ? b.slice(0, r) + ","
        + b.slice(r, len).match(/\d{3}/g).join(",") : b.slice(r, len)
        .match(/\d{3}/g).join(",");
}