最近对接一大堆接口，找了各种des加解密，很多都是php7以下的，要知道mcrypt_decrypt此类的方法再php7以上已经过时或废除了

Warning
This function has been DEPRECATED as of PHP 7.1.0 and REMOVED as of PHP 7.2.0. Relying on this function is highly discouraged.

搞了好久，好不容易看到了这个 https://blog.csdn.net/qq43599939/article/details/80226482 ，终于将C#、Java的代码转换成了php7的代码：

<?php

/**
 * Des加解密，兼容java、C#
 */
class Des
{

    /**
     * 加密
     * @author TechLee
     * @param  string $input
     * @param  string $key
     * @param  string $method
     * @param  string $iv
     * @return string
     */
    public static function encrypt($input, $key, $method = 'DES-ECB', $iv = null)
    {
        $iv = $iv ? $iv : self::createIv();
        return base64_encode(openssl_encrypt($input, $method, $key, OPENSSL_RAW_DATA, $method == 'DES-ECB' ? '' : $iv));
    }

    /**
     * 解密
     * @author TechLee
     * @param  string $input
     * @param  string $key
     * @param  string $method
     * @param  string $iv
     * @return string
     */
    public static function decrypt($input, $key, $method = 'DES-ECB', $iv = null)
    {
        $iv = $iv ? $iv : self::createIv();
        return openssl_decrypt(base64_decode($input), $method, $key, OPENSSL_RAW_DATA, $method == 'DES-ECB' ? '' : $iv);
    }

    /**
     * 这个玩意相当于java里的
     * byte[] iv = { 0, 0, 0, 0, 0,0, 0, 0 }
     * 也相当于C#里的
     * IV = new byte[8];
     * @author TechLee
     * @return [type] [description]
     */
    public static function createIv()
    {
        return self::hexToStr("0000000000000000");
    }

    public static function hexToStr($hex)
    {
        $string = '';
        for ($i = 0; $i < strlen($hex) - 1; $i += 2) {
            $string .= chr(hexdec($hex[$i] . $hex[$i + 1]));
        }
        return $string;
    }
}

关于des的模式有很多种,只有DES-ECB不需要iv

DES
DES-CBC
DES-CFB
DES-CFB1
DES-CFB8
DES-ECB
DES-EDE
DES-EDE-CBC
DES-EDE-CFB
DES-EDE-ECB
DES-EDE-OFB
DES-EDE3
DES-EDE3-CBC
DES-EDE3-CFB
DES-EDE3-CFB1
DES-EDE3-CFB8
DES-EDE3-ECB
DES-EDE3-OFB
DES-OFB
DES3
DESX
DESX-CBC

可以在线加解密验证

http://tool.chacuo.net/cryptdes

同时这里附上C#和java的代码

C#解密：

public static string DESDecrypt(string input, string key)
{
    System.Security.Cryptography.DESCryptoServiceProvider des = new System.Security.Cryptography.DESCryptoServiceProvider();
    des.Key = Encoding.UTF8.GetBytes(key);
    des.IV = new byte[8];
    System.Security.Cryptography.ICryptoTransform cTransform = des.CreateDecryptor(des.Key, des.IV);
    System.IO.MemoryStream mStream = new System.IO.MemoryStream();
    System.Security.Cryptography.CryptoStream cStream = new System.Security.Cryptography.CryptoStream(mStream, cTransform, System.Security.Cryptography.CryptoStreamMode.Write);
    byte[] byt = Convert.FromBase64String(input);
    cStream.Write(byt, 0, byt.Length);
    cStream.FlushFinalBlock();
    cStream.Close();
    return Encoding.UTF8.GetString(mStream.ToArray());
}

Java解密代码：

    public static String decode(byte[] DESkey, String data) throws Exception {
        DESKeySpec keySpec = new DESKeySpec(DESkey);// 设置密钥参数
         byte[] DESIV = { 0, 0, 0, 0, 0,0, 0, 0 };// 设置向量
        AlgorithmParameterSpec iv = new IvParameterSpec(DESIV);// 加密算法的参数接口，IvParameterSpec是它的一个实现
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");// 获得密钥工厂
        SecretKey key = keyFactory.generateSecret(keySpec);// 得到密钥对象

        Cipher deCipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
        deCipher.init(Cipher.DECRYPT_MODE, key, iv);
        BASE64Decoder base64Decoder = new BASE64Decoder();
        byte[] pasByte = deCipher.doFinal(base64Decoder.decodeBuffer(data));
        return new String(pasByte, "UTF-8");
    }