随机生成一串字符串

//随机生成一串字符串

function fn(len, charSet) {
    charSet = charSet || 'ABCDEFGHIJKLMAOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    var randomstr = '';
    for (var i = 0; i < len; i++) {
        var randomnum = Math.floor(Math.random() * charSet.length);
        randomstr += charSet.substring(randomnum, randomnum + 1);
    }
    console.log('获取到长度为' + len + '的随机字符串为：' + randomstr);
}
fn(10, '');