原文：https://www.cnblogs.com/lantor/p/7351372.html

<?php class AES { protected $cipher; protected $mode; protected $pad_method; protected $secret_key; protected $iv; public function __construct($key, $method = 'pkcs7', $iv = '', $mode = MCRYPT_MODE_ECB, $cipher = MCRYPT_RIJNDAEL_128) { $this->secret_key = $key; $this->pad_method =$method; $this->iv = $iv; $this->mode = $mode; $this->cipher = $cipher; } protected function pad_or_unpad($str, $ext) { if (!is_null($this->pad_method)) { $func_name = __CLASS__ . '::' . $this->pad_method . '_' . $ext . 'pad'; if (is_callable($func_name)) { $size = mcrypt_get_block_size($this->cipher, $this->mode); return call_user_func($func_name, $str, $size); } } return $str; } protected function pad($str) { return $this->pad_or_unpad($str, ''); } protected function unpad($str) { return $this->pad_or_unpad($str, 'un'); } public function encrypt($str) { $str = $this->pad($str); $td = mcrypt_module_open($this->cipher, '', $this->mode, ''); if (empty($this->iv)) { $iv = @mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND); } else { $iv = $this->iv; } mcrypt_generic_init($td, $this->secret_key, $iv); $cyper_text = mcrypt_generic($td, $str); $rt = base64_encode($cyper_text); mcrypt_generic_deinit($td); mcrypt_module_close($td); return $rt; } public function decrypt($str) { $td = mcrypt_module_open($this->cipher, '', $this->mode, ''); if (empty($this->iv)) { $iv = @mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND); } else { $iv = $this->iv; } mcrypt_generic_init($td, $this->secret_key, $iv); $decrypted_text = mdecrypt_generic($td, base64_decode($str)); $rt = $decrypted_text; mcrypt_generic_deinit($td); mcrypt_module_close($td); return $this->unpad($rt); } public static function pkcs7_pad($text, $blocksize) { $pad = $blocksize - (strlen($text) % $blocksize); return $text . str_repeat(chr($pad), $pad); } public static function pkcs7_unpad($text) { $pad = ord($text[strlen($text) - 1]); if ($pad > strlen($text)) return false; if (strspn($text, chr($pad), strlen($text) - $pad) != $pad) return false; return substr($text, 0, -1 * $pad); } } $aes = new AES('123456'); echo $aes->encrypt('凭栏知潇雨'), '<br>'; // We2MEs6x595hkFvSwtS05g== echo $aes->decrypt('We2MEs6x595hkFvSwtS05g=='); // 凭栏知潇雨