计算字符串的字节长度

String.prototype.len = function () {

    return this.replace(/[^\x00-\xff]/g, 'xx').length;

};

alert(t.Calendar.len());

//保留两位小数

        //功能：将浮点数四舍五入，取小数点后2位

        function toDecimal(x) {

            var f = parseFloat(x);

            if (isNaN(f)) {

                return;

            }

            f = Math.round(x*100)/100;

            return f;

        }

function toDecimal2(x) {

            var f = parseFloat(x);

            if (isNaN(f)) {

                return false;

            }

            var f = Math.round(x*100)/100;

            var s = f.toString();

            var rs = s.indexOf('.');

            if (rs < 0) {

                rs = s.length;

                s += '.';

            }

            while (s.length <= rs + 2) {

                s += '0';

            }

            return s;

        }