private void OptionValidateDocument_Click(object sender, EventArgs e)
        {
            try
            {
                string toValidate = UploadedDocumentClass.GetFileContent();

                DigitalSignatureClass signObject = new DigitalSignatureClass();
                bool isValid = signObject.ValidateDocument(toValidate);

                LoadingScreenForm loadScreen = new LoadingScreenForm(UploadedDocumentClass.GetFileName(), "Validating Signature");
                loadScreen.ShowDialog();

                if (isValid)
                {
                    MessageBox.Show("Signature is VALID", "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
                }
                else
                {
                    MessageBox.Show("Signature is NOT valid", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
            catch
            {
                MessageBox.Show("Signature is NOT valid", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }
        private void OptionSignDocument_Click(object sender, EventArgs e)
        {
            string toSign = UploadedDocumentClass.GetFileContent();

            DigitalSignatureClass signObject = new DigitalSignatureClass();
            string signedDocument            = signObject.SignDocument(toSign);

            LoadingScreenForm loadScreen = new LoadingScreenForm(UploadedDocumentClass.GetFileName(), "Digital Signature");

            loadScreen.ShowDialog();

            SaveToTxt("helpfile_signature", signedDocument + "\r\n" + toSign);

            outputScreen.Text  = "SHA1 digest: \r\n" + signObject.GetDigestForSign();
            outputScreen.Text += "\r\n\r\nSigned document: \r\n" + signedDocument;
        }