c#中MD5方法总结

/// <summary>

/// 32位md5

/// </summary>

/// <param name="str"></param>

/// <returns></returns>

public static string GetBigMd5(string str)

{

string cl = str;

string pwd = "";

var md5 = MD5.Create();

byte[] s = md5.ComputeHash(Encoding.UTF8.GetBytes(cl));

for (int i = 0; i < s.Length; i++)

{

pwd = pwd + s[i].ToString("X2");

}

return pwd;

}

/// <summary>

/// 16位MD5

/// </summary>

/// <param name="str"></param>

/// <returns></returns>

public static string GetSmallMd5(string str)

{

var md5 = new MD5CryptoServiceProvider();

string t2 = BitConverter.ToString(md5.ComputeHash(UTF8Encoding.Default.GetBytes(str)), 4, 8);

t2 = t2.Replace("-", "");

return t2;

}

private static string Encrypt(string strInput)

{

int i;

int len = strInput.Length;

string strFont = strInput.Remove(len - 1, 1);

string strEnd = strInput.Remove(0, len - 1);

var charFont = strFont.ToCharArray();

for (i = 0; i < strFont.Length; i++)

{

int intFont = (int)charFont[i] + 3;

charFont[i] = Convert.ToChar(intFont);

}

strFont = ""; //let strFont null

for (i = 0; i < charFont.Length; i++)

{

strFont += charFont[i];

}

var strOutput = strEnd + strFont;

return strOutput;

}

private static string Decrypt(string strInput)

{

int i;

string strFont = strInput.Remove(0, 1);

string strEnd = strInput.Remove(1);