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PHP implements generating random codes

Mar 15, 2018 pm 05:25 PM
phpgeneraterandom


本文主要和大家分享PHP实现生成随机码,小伙伴让写一个生成5位随机码的函数,要求:可包含数字、字母大小写,代码尽量短。

解题思路

(1) . 第一思路

都是印象中匹配ASCII码进行随机读取的实现方法,此处可提供一个方法作为参考:

function get_rand_ascii($pw_length = 5){
        $randpwd = '';        
        for ($i = 0; $i < $pw_length; $i++) 
        {            $randpwd .= chr(mt_rand(33, 99));
        }        return $randpwd;
    }

(2) . 第二思路

1.定义随机数组,内含能够使用的所有字符

function getRandomString($length=5) {
    //可任意添加需要的字符
    $chars = array(        "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k",        "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v",        "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G",        "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R",        "S", "T", "U", "V", "W", "X", "Y", "Z", "0", "1", "2",        "3", "4", "5", "6", "7", "8", "9"
    );    $charsLen = count ( $chars ) - 1;
    shuffle ( $chars ); // 将数组打乱
    $output = "";    for($i = 0; $i < $length; $i ++)
     {        $output .= $chars [mt_rand ( 0, $charsLen )];
    }    return $output;
}
  • 提示:此类的代码,建议去除可能引起歧义的字符,如:1、I、l、0、o、O、9、q.
     缺点:5个字符没有重复

2.比较上述 1 中的数组形式,设计字符串形式参考如下:

function get_pass( $length = 8 ) {
        // 密码字符集,可任意添加你需要的字符
        $chars = &#39;abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()-_ []{}<>~`+=,.;:/?|&#39;;       
         $password = &#39;&#39;;        for ( $i = 0; $i < $length; $i++ ) {            // 这里提供两种字符获取方式
            // 第一种是使用 substr 截取$chars中的任意一位字符;
            // 第二种是取字符数组 $chars 的任意元素
            // $password .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
            $password .= $chars[ mt_rand(0, strlen($chars) - 1) ];
        }        return $password;
    }

(3) . 第三思路

发现的新思路,可使用加密算法进行获取

public function getRand(){
        $rand = rand(10000,100000);       
         $str = substr(base64_encode($rand), 0, 5);        return $str;
    }
  • 提示:md5()函数只有数字和小写的字母
     发现:base64_encode()可以满足要求

拓展延伸

  • 针对于PHP设计,一般的随机码可用于验证码、分享码的生成,着重注意位数的限制,必要情况下,保证该随机码的唯一性.

  • password_hash 的使用(PHP>5.5)
    可用于用户的密码加密存储,不过有一点需注意:如果数据库迁移,对于java或.net语言将难以适用.

$password = &#39;password1232456&#39;;//前端 获取的原始密码
        //数据库存放的 使用BCRYPT算法加密的密码
        //此处仅为测试,实际应用时应从数据表中查询获得
        //$db_pass = &#39;$2y$10$2vJJC.rb/swAUnTfc9B94.l/ix75kiZHvOZFpu0Dd8uzp07YWlj4q&#39;;
        $db_pass = password_hash($password, PASSWORD_BCRYPT);        if (password_verify($password , $db_pass)){            echo "密码匹配";
        }else{            echo "密码错误";
        }

相关推荐:

php生成随机码的一段代码

php生成字符串随机码实现方法

php生成一个可选位数的随机码

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