javascript根据时间生成m位随机数最大13位

function ran(m) {m = m > 13 ? 13 : m;var num = new Date().getTime();return num.toString().substring(13 - m);}console.log(ran(5));

function rand(m) {m = m > 16 ? 16 : m;var num = Math.random().toString();if(num.substr(num.length - m, 1) === '0') {return rand(m);}return num.substring(num.length - m);}console.log(rand(5));

function rando(m) {var num = '';for(var i = 0; i < m; i++) {var val = parseInt(Math.random()*10, 10);if(i === 0 && val === 0) {i--;continue;}num += val;}return num;}console.log(rando(5));