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Digital signature position

It´s possible to get a existent PDF file and choose the position (END) of the Digital Signature ?
Because in your example, I create a new Blank Page and add the digital signature to this new page. So, if it´s a PDF file with 2 pages, will be 3 and the first 2 pages we will not have any signature or "check".

For example:
1) The user upload a PDF file with 2 pages
2) The user read the document
3) He wants to Digital Sign the document.
4) The app open the "Whitescreen" to sign
5) I put this signature (Image) at the End of the existent uploaded PDF file (still 2 pages).

5 Replies 1 reply marked as answer
SL Sowmiya Loganathan Syncfusion Team June 10, 2020 12:56 PM UTC

Hi Marcelo,    
   
Thank you for contacting Syncfusion support.    
   
We have analyzed your requirement. If your requirement is to add a digital signature in a new page (added page) of PDF document, please refer the below sample for your reference,    
   
   
Note: You can set the bounds of the signature by using the below code snippet,    
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);   
  
If this is not your requirement, please let us know further details about your requirement. It will helpful for us to provide a precise solution to this.    
 
Regards, 
Sowmiya Loganathan 


MC marcelo couto fernandes June 11, 2020 12:01 AM UTC

Hi, 

As I´ve told you, I need to add the signature to a existent page of a PDF file. Not to a new page.
I  saw this example before, but it doesn´t is what I need. I upload a file and add the signature to the beginning or end of one page (first or last for example)

Thanks.

SL Sowmiya Loganathan Syncfusion Team June 11, 2020 11:26 AM UTC

Hi Marcelo,   
  
Thank you for the details.   
  
Please find the below code snippet to add digital signature in starting of the last page in PDF document.   
  
//Load the file as stream  
Stream docStream =typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("GettingStarted.Assets.BlankPDF-merged.pdf");  
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);  
  
//Get the last page of PDF document   
PdfLoadedPage loadedPage = loadedDocument.Pages[loadedDocument.Pages.Count - 1] asPdfLoadedPage;  
  
//Creates a certificate instance from PFX file with private key  
Stream certificateStream =typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("GettingStarted.Assets.PDF.pfx");  
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");  
  
//Creates a digital signature  
PdfSignature signature = new PdfSignature(loadedDocument, loadedPage, pdfCert, "Signature");  
  
//Load the image file  
Stream imageStream =typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("GettingStarted.Assets.logo.png");  
  
//Sets an image for signature field  
PdfBitmap signatureImage = new PdfBitmap(imageStream);  
  
//Sets signature information  
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);  
signature.ContactInfo = "[email protected]";  
signature.LocationInfo = "Honolulu, Hawaii";  
signature.Reason = "I am author of this document.";  
  
//Draws the signature image  
loadedPage.Graphics.DrawImage(signatureImage, 0, 0);  
  
//Save the document to the stream  
MemoryStream stream = new MemoryStream();  
loadedDocument.Save(stream);  
                                                                    
  
Please try the above solution in your end and let us know the result.   
  
Regards,   
Sowmiya Loganathan  
 


Marked as answer
MA Marcelo replied to Sowmiya Loganathan June 11, 2020 02:00 PM UTC

Hi Marcelo,   
  
Thank you for the details.   
  
Please find the below code snippet to add digital signature in starting of the last page in PDF document.   
  
//Load the file as stream  
Stream docStream =typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("GettingStarted.Assets.BlankPDF-merged.pdf");  
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);  
  
//Get the last page of PDF document   
PdfLoadedPage loadedPage = loadedDocument.Pages[loadedDocument.Pages.Count - 1] asPdfLoadedPage;  
  
//Creates a certificate instance from PFX file with private key  
Stream certificateStream =typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("GettingStarted.Assets.PDF.pfx");  
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");  
  
//Creates a digital signature  
PdfSignature signature = new PdfSignature(loadedDocument, loadedPage, pdfCert, "Signature");  
  
//Load the image file  
Stream imageStream =typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("GettingStarted.Assets.logo.png");  
  
//Sets an image for signature field  
PdfBitmap signatureImage = new PdfBitmap(imageStream);  
  
//Sets signature information  
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);  
signature.ContactInfo = "[email protected]";  
signature.LocationInfo = "Honolulu, Hawaii";  
signature.Reason = "I am author of this document.";  
  
//Draws the signature image  
loadedPage.Graphics.DrawImage(signatureImage, 0, 0);  
  
//Save the document to the stream  
MemoryStream stream = new MemoryStream();  
loadedDocument.Save(stream);  
                                                                    
  
Please try the above solution in your end and let us know the result.   
  
Regards,   
Sowmiya Loganathan  
 


Thanks. I will give a try.
But, can I choose where will be setted the image of the signature ?
Above you put the image, but doesn´t set where...

loadedDocument.Save(stream); 

SL Sowmiya Loganathan Syncfusion Team June 12, 2020 01:26 PM UTC

Hi Marcelo,   
  
You can draw the image anywhere in PDF document by specifying the position(PointF) or bounds(RectangleF). Please refer the below code snippet,   
  
//Sets signature information  
signature.Bounds = new RectangleF(0,0,200,100);  
  
//Draws the signature image in page graphics   
loadedPage.Graphics.DrawImage(signatureImage, signature.Bounds);  
   
Also, you can draw the image in signature appearance and please refer the below code snippet for more details,   
  
//Sets signature information  
signature.Bounds = new RectangleF(0,0,200,100);  
  
//Draw image in signature appearance   
signature.Appearance.Normal.Graphics.DrawImage(signatureImage, new RectangleF(0, 0, 200, 100));  
  
Please let us know if you need any further assistance on this.   
  
Regards,  
Sowmiya Loganathan  
 


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