php 生成随机帐号密码邮箱

 先创建一个方法

$username = get_new_user($con);

这个方法先生成一个随机帐号，然后去数据库查询是否已经有了 如果有了就再次递归调用本方法

注意 这个递归在错误的时候没有出口，所以请求该接口的时候应当设置超时退出

function get_new_user($con)
{

    //获取唯一用户名 如果存在就再次随机查询
    $user_name = randStr();

    $sql = "select * from `user` where `username`='{$user_name}'";
    if (!$obj = mysqli_query($con, $sql)) {
        $resData['msg'] = mysqli_errno($con) . $sql;
        $resData['status'] = false;
        $res = json_encode($resData, true);
        exit($res);
    }
    if (mysqli_affected_rows($con) == 0) {
        return $user_name;
    } else {
        get_new_user($con);
    }
}

核心方法来了

function randStr($len = 6, $format = 'default')
{
    switch ($format) {
        case 'ALL':
            $chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-@#~';
            break;
        case 'CHAR':
            $chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-@#~';
            break;
        case 'NUMBER':
            $chars = '0123456789';
            break;
        default :
            $chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
            break;
    }
    mt_srand((double)microtime() * 1000000 * getmypid());
    $password = "";
    while (strlen($password) < $len)
        $password .= substr($chars, (mt_rand() % strlen($chars)), 1);
    return $password;
}

邮箱和密码的生成更为简单

$password = randStr();
    $email = $key_type . randStr() . "@fake.com";