MD5加密封装

加密32位

 /// <summary>
        /// MD5字符串加密
        /// </summary>
        /// <param name="txt"></param>
        /// <returns>加密后字符串</returns>
        public static string GenerateMD5(string txt)
        {
            using (MD5 mi = MD5.Create())
            {
                byte[] buffer = Encoding.Default.GetBytes(txt);
                //开始加密
                byte[] newBuffer = mi.ComputeHash(buffer);
                StringBuilder sb = new StringBuilder();
                for (int i = 0; i < newBuffer.Length; i++)
                {
                    sb.Append(newBuffer[i].ToString("x2"));
                }
                return sb.ToString();
            }
        }

1.固定返回固定长度字符串（16位或者32位）

/// <summary>
/// 用MD5加密字符串，可选择生成16位或者32位的加密字符串
/// </summary>
/// <param name="password">待加密的字符串</param>
/// <param name="bit">位数，一般取值16 或 32</param>
/// <returns>返回的加密后的字符串</returns>
public string MD5Encrypt(string password, int bit)
{
MD5CryptoServiceProvider md5Hasher = new MD5CryptoServiceProvider();
byte[] hashedDataBytes;
hashedDataBytes = md5Hasher.ComputeHash(Encoding.GetEncoding("gb2312").GetBytes(password));
StringBuilder tmp = new StringBuilder();
foreach (byte i in hashedDataBytes)
{
tmp.Append(i.ToString("x2"));
}
if (bit == 16)
return tmp.ToString().A(8, 16);
else
if (bit == 32) return tmp.ToString();//默认情况
else return string.Empty;
}

 2. 加密字符串

/// <summary>
/// 用MD5加密字符串
/// </summary>
/// <param name="password">待加密的字符串</param>
/// <returns></returns>
public string MD5Encrypt(string password)
{
MD5CryptoServiceProvider md5Hasher = new MD5CryptoServiceProvider();
byte[] hashedDataBytes;
hashedDataBytes = md5Hasher.ComputeHash(Encoding.GetEncoding("gb2312").GetBytes(password));
StringBuilder tmp = new StringBuilder();
foreach (byte i in hashedDataBytes)
{
tmp.Append(i.ToString("x2"));
}
return tmp.ToString();
}