Md5

string GetHash(string usedString)
{ //Create a Hash to send to server
    var md5 = new MD5CryptoServiceProvider();
    byte[] bytes = Encoding.UTF8.GetBytes(usedString + secretKey);
    byte[] hash = md5.ComputeHash(bytes);
 
    StringBuilder sb = new StringBuilder();
    for (int i = 0; i < hash.Length; i++)
    {
        sb.Append(hash[i].ToString("x2"));
    }
    return sb.ToString();
}

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