加密类

#region ========加密========
/// <summary>
/// 加密
/// </summary>
/// <param name="Text"></param>
/// <returns></returns>
public static string Encrypt(string Text)
{
    return Encrypt(Text, "cong");
}
/// <summary> 
/// 加密数据 
/// </summary> 
/// <param name="Text"></param> 
/// <param name="sKey"></param> 
/// <returns></returns> 
public static string Encrypt(string Text, string sKey)
{
    DESCryptoServiceProvider des = new DESCryptoServiceProvider();
    byte[] inputByteArray;
    inputByteArray = Encoding.Default.GetBytes(Text);
    des.Key = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
    des.IV = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
    System.IO.MemoryStream ms = new System.IO.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();
}

#endregion


#region ========解密========


/// <summary>
/// 解密
/// </summary>
/// <param name="Text"></param>
/// <returns></returns>
public static string Decrypt(string Text)
{
    return Decrypt(Text, "cong");
}
/// <summary> 
/// 解密数据 
/// </summary> 
/// <param name="Text"></param> 
/// <param name="sKey"></param> 
/// <returns></returns> 
public static string Decrypt(string Text, string sKey)
{
    DESCryptoServiceProvider des = new DESCryptoServiceProvider();
    int len;
    len = Text.Length / 2;
    byte[] inputByteArray = new byte[len];
    int x, i;
    for (x = 0; x < len; x++)
    {
        i = Convert.ToInt32(Text.Substring(x * 2, 2), 16);
        inputByteArray[x] = (byte)i;
    }
    des.Key = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
    des.IV = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
    System.IO.MemoryStream ms = new System.IO.MemoryStream();
    CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
    cs.Write(inputByteArray, 0, inputByteArray.Length);
    cs.FlushFinalBlock();
    return Encoding.Default.GetString(ms.ToArray());
}

#endregion

在.net 4.5版本下，使用System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile进行MD5加密时，会出现已过时,如下图：

MD5加密过时显示.png

我们可以用下面的方法替代之：

命名空间:System.Web.Security程序集:System.Web（在 system.web.dll 中）

/// <summary>
/// 32位MD5加密
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
private static string Md5Hash(string input)
{
MD5CryptoServiceProvider md5Hasher = new MD5CryptoServiceProvider();
byte[] data = md5Hasher.ComputeHash(Encoding.Default.GetBytes(input));
StringBuilder sBuilder = new StringBuilder();
for (int i = 0; i < data.Length; i++)
{
    sBuilder.Append(data[i].ToString("x2"));
}
return sBuilder.ToString();
}