c# MD5

 static public string GetMD5WithFilePath(string filePath)
        {
            FileStream file = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read);
            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
            byte[] hash_byte = md5.ComputeHash(file);
            string str = System.BitConverter.ToString(hash_byte);
            str = str.Replace("-", "");
            return str;
        }