[PHP知识库]php 一个简单的非标准ascall码 加密解密方法

可以加入一个数字进行运算，加密解密

//ascii 不对称加密
function encode_ascii($str){
  $c = $str;
  $offset = 2762;//需要计算的数，可自定义
  $len = strlen($c);//字符串长度
//echo $len;
//die();
   $a = 0;
   $scill = '';
   while ($a < $len) {

        $ud = ord($c{$a}) + $offset;
        $dec = $ud;
        $utf = '';
        if ($dec < 128) {
            $utf .= chr($dec);
        } else if ($dec < 2048) {
            $utf .= chr(192 + (($dec - ($dec % 64)) / 64));
            $utf .= chr(128 + ($dec % 64));
        } else {
            $utf .= chr(224 + (($dec - ($dec % 4096)) / 4096));
            $utf .= chr(128 + ((($dec % 4096) - ($dec % 64)) / 64));
            $utf .= chr(128 + ($dec % 64));
        }
//    echo $utf."<br>";

        $scill .= $utf;
        $a += 1;
    }
//    echo $scill;

     $scill = base64_encode($scill);// 加密
//     echo $scill;
//     echo "<br>";
     $scill2 = strrev($scill);//反转字符串

    return $scill2;
}

//ascii 不对称加密的解密
function decode_ascii($str){

    $offset = 2762;

    $scill = strrev($str);//反转
    $c = base64_decode($scill);//解密

    $len = strlen($c);
//    echo 'len: '.$len."<br>";
    $a = 0;
    $scill =  '';
    while ($a < $len) {

        $ud = 0;
        if (ord($c{$a}) >= 0 && ord($c{$a}) <= 127) {
            $ud = ord($c{$a}) - $offset;
            $a += 1;
        } else if (ord($c{$a}) >= 192 && ord($c{$a}) <= 223) {
            $ud = (ord($c{$a}) - 192) * 64 + (ord($c{$a + 1}) - 128) - $offset;
            $a += 2;
        } else if (ord($c{$a}) >= 224 && ord($c{$a}) <= 239) {
            $ud = (ord($c{$a}) - 224) * 4096 + (ord($c{$a + 1}) - 128) * 64 + (ord($c{$a + 2}) - 128) - $offset;
            $a += 3;
        } else if (ord($c{$a}) >= 240 && ord($c{$a}) <= 247) {
            $ud = (ord($c{$a}) - 240) * 262144 + (ord($c{$a + 1}) - 128) * 4096 + (ord($c{$a + 2}) - 128) * 64 + (ord($c{$a + 3}) - 128) - $offset;
            $a += 4;
        } else if (ord($c{$a}) >= 248 && ord($c{$a}) <= 251) {
            $ud = (ord($c{$a}) - 248) * 16777216 + (ord($c{$a + 1}) - 128) * 262144 + (ord($c{$a + 2}) - 128) * 4096 + (ord($c{$a + 3}) - 128) * 64 + (ord($c{$a + 4}) - 128) - $offset;
            $a += 5;
        } else if (ord($c{$a}) >= 252 && ord($c{$a}) <= 253) {
            $ud = (ord($c{$a}) - 252) * 1073741824 + (ord($c{$a + 1}) - 128) * 16777216 + (ord($c{$a + 2}) - 128) * 262144 + (ord($c{$a + 3}) - 128) * 4096 + (ord($c{$a + 4}) - 128) * 64 + (ord($c{$a + 5}) - 128) - $offset;
            $a += 6;
        } else if (ord($c{$a}) >= 254 && ord($c{$a}) <= 255) { //error
            $ud = false;
        }
//        echo $ud .' : '.chr($ud)."<br>";
//        $scill .= $ud ;//十进制
        $scill .= chr($ud) ;

    }

    return $scill;
        
}

$offset 是用来计算的数字

例子

$uid = "190457545";
$sci = "/uK4+uK4/uK4ByK4/uK4+uK46uK4DyK47uK4";
echo $sci." 解密后 ". decode_ascii($sci);?
echo $uid.' 加密后 '.encode_ascii($uid);