asp.net实现的DES加密解密操作示例

//加密方法
private string encrypt(string strToEncrypt)
{
 if (strToEncrypt == null || strToEncrypt == "") return strToEncrypt;
 DESCryptoServiceProvider des = new DESCryptoServiceProvider();
 //把字符串放到byte数组中，主意编码方式
 byte[] inputByteArray = Encoding.Default.GetBytes(strToEncrypt);
 //建立加密对象的密钥和偏移量
 des.Key = new byte[] { 1, 3, 5, 7, 2, 4, 6, 8 };
 des.Mode = CipherMode.ECB;
 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);
 }
 return ret.ToString();
}
//解密方法
private string Decrypt(string pToDecrypt)
{
 if (pToDecrypt == null || pToDecrypt == "") return pToDecrypt;
 try
 {
 DESCryptoServiceProvider des = new DESCryptoServiceProvider();
 //Put the input string into the byte array
 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;
 }
 //key
 des.Key = new byte[] { 1, 3, 5, 7, 2, 4, 6, 8 }; ;
 //des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
 des.Mode = CipherMode.ECB;
 MemoryStream ms = new MemoryStream();
 CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
 cs.Write(inputByteArray, 0, inputByteArray.Length);
 cs.FlushFinalBlock();
 //建立StringBuild对象，CreateDecrypt使用的是流对象，必须把解密后的文本变成流对象
 StringBuilder ret = new StringBuilder();
 return System.Text.Encoding.Default.GetString(ms.ToArray());
 }
 catch (Exception Exp)
 {
 return String.Empty;
 }
}