Update Program.cs

Author: chinnumuniyappan

Digital Signature/Multiple-digital-signature/.NET/Multiple-digital-signature/Program.cs

@@ -3,43 +3,59 @@
 using Syncfusion.Pdf.Security;
 using Syncfusion.Pdf;
 
-//Load an existing PDF document. 
+// Open the existing PDF document.
 PdfLoadedDocument loadedDocument = new PdfLoadedDocument(Path.GetFullPath(@"Data/SignatureFields.pdf"));
-//Get the first page of the document.
+
+// Retrieve the first page from the PDF document.
 PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
-//Get the first signature field of the PDF document.
+
+// Access the first signature field available in the PDF form.
 PdfLoadedSignatureField signatureField1 = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
-//Create a certificate instance from a PFX file with a private key.
+
+// Create a certificate object using the PFX file and its password.
 PdfCertificate certificate1 = new PdfCertificate(Path.GetFullPath(@"Data/PDF.pfx"), "syncfusion");
-//Add a signature to the signature field.
-signatureField1.Signature = new PdfSignature(loadedDocument, page, certificate1, "Signature", signatureField1);
-//Set an image for the signature field.
+
+// Digitally sign the first signature field.
+signatureField1.Signature = new PdfSignature(loadedDocument, page, certificate1, "Signature1", signatureField1);
+
+// Load the signature image for the first signer.
 FileStream imageStream1 = new FileStream(Path.GetFullPath(@"Data/Student Signature.jpg"), FileMode.Open, FileAccess.Read);
+
 PdfBitmap signatureImage = new PdfBitmap(imageStream1);
-imageStream1.Position = 0;
-//Insert an image in the signature appearance. 
+
+
+// Render the signature image within the signature field appearance.
 signatureField1.Signature.Appearance.Normal.Graphics.DrawImage(signatureImage, 0, 0, signatureField1.Bounds.Width, signatureField1.Bounds.Height);
-//Save the document into the stream.
+
+// Save the signed PDF into a memory stream.
 MemoryStream stream = new MemoryStream();
 loadedDocument.Save(stream);
-//Close the PDF document
+
+// Close the original PDF document instance.
 loadedDocument.Close(true);
-stream.Position = 0;
-//Load the signed PDF document.
+
+// Reopen the partially signed PDF from the memory stream.
 PdfLoadedDocument signedDocument = new PdfLoadedDocument(stream);
-//Load the PDF page.
+
+// Retrieve the first page of the signed document.
 PdfLoadedPage loadedPage = signedDocument.Pages[0] as PdfLoadedPage;
-//Get the first signature field of the PDF document.
+
+// Access the second signature field in the PDF form.
 PdfLoadedSignatureField signatureField2 = signedDocument.Form.Fields[1] as PdfLoadedSignatureField;
-//Add a signature to the signature field. 
-signatureField2.Signature = new PdfSignature(signedDocument, loadedPage, certificate1, "Signature", signatureField2);
-//Set an image for the signature field.
+
+// Apply a digital signature to the second signature field.
+signatureField2.Signature = new PdfSignature(signedDocument, loadedPage, certificate1, "Signature2", signatureField2);
+
+// Load the signature image for the second signer.
 FileStream imageStream2 = new FileStream(Path.GetFullPath(@"Data/Teacher Signature.png"), FileMode.Open, FileAccess.Read);
+
 PdfBitmap signatureImage1 = new PdfBitmap(imageStream2);
-imageStream2.Position = 0;
-//Draw an image in the signature appearance. 
+
+// Display the signature image in the second signature field appearance.
 signatureField2.Signature.Appearance.Normal.Graphics.DrawImage(signatureImage1, 0, 0, signatureField2.Bounds.Width, signatureField2.Bounds.Height);
-//Save the PDF document
+
+// Save the fully signed PDF document.
 signedDocument.Save(Path.GetFullPath(@"Output/Output.pdf"));
-//Close the PDF document
-signedDocument.Close(true);
+
+// Close the signed PDF document.
+signedDocument.Close(true);