php des 对称加解密类

<?php
header("Content-Type: text/html;charset=utf-8");
/**
* des 对称加解密
*/
class des {
	private $key = '';
	private $cipher = MCRYPT_DES; //加解密算法
	private $modes = MCRYPT_MODE_ECB; //算法模式
	private $iv = ''; //初始化向量
	/**
	 * 密钥
	 */
	public function __construct($key) {
		$this->key = $key;
		$this->iv = mcrypt_create_iv(mcrypt_get_iv_size($this->cipher,$this->modes),MCRYPT_RAND);
	}
	/**
	 * 加密
	 */
	public function encrypt($input) {
		return mcrypt_encrypt($this->cipher,$this->key,$input,$this->modes,$this->iv);
	}
	/**
	 * 解密
	 */
	public function decrypt($input) {
		return mcrypt_decrypt($this->cipher,$this->key,$input,$this->modes,$this->iv); //解密函数
	}
}

$des = new des(100);
$a = $des->encrypt('郭海明');
echo $des->decrypt($a);