DES加解密演算法，在C#與PHP中的通用類。

注意：

1、類中的祕鑰key跟向量iv，均用的同樣的值

2、編碼均採用的utf-8

以下為具體程式碼，可以直接複製去進行實際測試

C#版程式碼：

using System;   
using System.Data;   
using System.Configuration;   
using System.Web;   
using System.Web.Security;   
using System.Web.UI;   
using System.Web.UI.WebControls;   
using System.Web.UI.WebControls.WebParts;   
using System.Web.UI.HtmlControls;   
using System.Data.SqlClient;   
using System.Security.Cryptography;   
using System.IO;   
using System.Text;  

//C# 版DES 加解密演算法類
public class Des{   
    //加解密金鑰
    private static  string skey = "12345678";
	
	#region DESEnCode DES加密   
	public static string DESEnCode(string pToEncrypt, string sKey)   
	{   
		pToEncrypt = HttpContext.Current.Server.UrlEncode(pToEncrypt);   
		DESCryptoServiceProvider des = new DESCryptoServiceProvider();   
		byte[] inputByteArray = Encoding.GetEncoding("UTF-8").GetBytes(pToEncrypt);   
    
		des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);   
		des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);   
		MemoryStream ms = new MemoryStream();   
		CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);   
   
		cs.Write(inputByteArray, 0, inputByteArray.Length);   
		cs.FlushFinalBlock();   
   
		StringBuilder ret = new StringBuilder();   
		foreach (byte b in ms.ToArray())   
		{   
			ret.AppendFormat("{0:X2}", b);   
		}   
		ret.ToString();   
		return ret.ToString();   
	}  
	#endregion  
	
	#region DESDeCode DES解密
	public static string DESDeCode(string pToDecrypt, string sKey)
	{
		DESCryptoServiceProvider des = new DESCryptoServiceProvider();
		byte[] inputByteArray = new byte[pToDecrypt.Length / 2];
		for (int x = 0; x < pToDecrypt.Length / 2; x++)
		{
			int i = (Convert.ToInt32(pToDecrypt.Substring(x * 2, 2), 16));
			inputByteArray[x] = (byte)i;
		}
 
		des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
		des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
		MemoryStream ms = new MemoryStream();
		CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
		cs.Write(inputByteArray, 0, inputByteArray.Length);
		cs.FlushFinalBlock();
 
		StringBuilder ret = new StringBuilder();
 
		return HttpContext.Current.Server.UrlDecode(System.Text.Encoding.Default.GetString(ms.ToArray()));
	}
    #endregion 
}     
 

<?php
//PHP 版DES 加解密演算法類
class DES {
	var $key;
	var $iv; //偏移量
	
	function __construct($key) {
		//key長度為8位,例如:1234abcd
		$this->key = $key;
		$this->iv = $key; //預設以$key 作為 iv
	}
	
	//加密
	function encrypt($str) {
		$size = mcrypt_get_block_size ( MCRYPT_DES, MCRYPT_MODE_CBC );
		$str = $this->pkcs5Pad ( $str, $size );
		return strtoupper( bin2hex( mcrypt_cbc(MCRYPT_DES, $this->key, $str, MCRYPT_ENCRYPT, $this->iv ) ) );
	}
	
	//解密
	function decrypt($str) {
		$strBin = $this->hex2bin( strtolower( $str ) );
		$str = mcrypt_cbc( MCRYPT_DES, $this->key, $strBin, MCRYPT_DECRYPT, $this->iv );
		$str = $this->pkcs5Unpad( $str );
		return $str;
	}
	
	function hex2bin($hexData) {
		$binData = "";
		for($i = 0; $i < strlen ( $hexData ); $i += 2) {
			$binData .= chr ( hexdec ( substr ( $hexData, $i, 2 ) ) );
		}
		return $binData;
	}

	function pkcs5Pad($text, $blocksize) {
		$pad = $blocksize - (strlen ( $text ) % $blocksize);
		return $text . str_repeat ( chr ( $pad ), $pad );
	}
	
	function pkcs5Unpad($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 );
	}
}

header("Content-type: text/html; charset=utf-8");
$key = '12345678';
$str = 'abc.123';
$des = new DES($key);
$str_en_des = $des->encrypt($str); //加密字串
$str_de_des = $des->decrypt($str_en_des); //解密字串
echo '加密字串：',$str,'<br>';
echo '加密祕鑰key：',$key,'<br><br>';
echo '加密後字串：',$str_en_des,'<br>';
echo '解密後字串：',$str_de_des,'<br>';

?>