MD5 加密 字符串

     //获取字符串的MD5码
        public  string CreateMD5Hash(string input)
        {
            // Use input string to calculate MD5 hash
            System.Security.Cryptography.MD5 md5 = System.Security.Cryptography.MD5.Create();
            byte[] inputBytes = System.Text.Encoding.ASCII.GetBytes(input);
            byte[] hashBytes = md5.ComputeHash(inputBytes);

            // Convert the byte array to hexadecimal string
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < hashBytes.Length; i++)
            {
                sb.Append(hashBytes[i].ToString("X2"));
                // To force the hex string to lower-case letters instead of
                // upper-case, use he following line instead:
                // sb.Append(hashBytes[i].ToString("x2")); 
            }
            return sb.ToString();
        }