配合java程序接口的架接，java那边需要我这边对传过去的值进行AES对称加密，接口返回的结果也是加密过的（就要用到解密），然后试了很多办法，也一一对应了AES的key密钥值，偏移量（IV）的值，都还是不能和java加密解密的结果一样。接着我就去找了一些文档，结果发现PHP里面补码方式只有：ZeroPadding这一种方式，而java接口那边是用PKCS5Padding补码方式，发现了问题所在，就编写了如下PHP实现AES/CBC/PKCS5Padding的加密解密方式。如有错误，还请指正！

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     iv;11         $encryptKey = $this->encryptKey;12  13         //Open module14         $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, $localIV);15  16         //print "module = $module 
" ;17  18         mcrypt_generic_init($module, $encryptKey, $localIV);19  20         //Padding21         $block = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC);22         $pad = $block - (strlen($encryptStr) % $block); //Compute how many characters need to pad23         $encryptStr .= str_repeat(chr($pad), $pad); // After pad, the str length must be equal to block or its integer multiples24  25         //encrypt26         $encrypted = mcrypt_generic($module, $encryptStr);27  28         //Close29         mcrypt_generic_deinit($module);30         mcrypt_module_close($module);31  32         return base64_encode($encrypted);33  34     }35  36     //解密37     public function decrypt($encryptStr) {38         $localIV = $this->iv;39         $encryptKey = $this->encryptKey;40  41         //Open module42         $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, $localIV);43  44         //print "module = $module 
" ;45  46         mcrypt_generic_init($module, $encryptKey, $localIV);47  48         $encryptedData = base64_decode($encryptStr);49         $encryptedData = mdecrypt_generic($module, $encryptedData);50  51         return $encryptedData;52     }53 }54 $encryptString = 'gz1DR+BsCzQe55HFdq1IiQ==';55 $encryptObj = new MagicCrypt();56  57 $result = $encryptObj->encrypt($encryptString);//加密结果58 $decryptString = $decryptString = $encryptObj->decrypt($result);//解密结果59 echo $result . "
";60 echo $decryptString . "
";61 ?>