view pdf and add custom stamp image on it

You can load the base64 string using the LEADDocument class, and then display the PDF using the DocumentViewer class which is showed in the documentation below. Here is how you can first handle the loading of the PDF from Base64:

static LEADDocument LEADDocumentFrom64(string b64Str)
{
byte[] bytes = Convert.FromBase64String(b64Str);
using (MemoryStream ms = new MemoryStream(bytes))
{
return DocumentFactory.LoadFromStream(ms, new LoadDocumentOptions());
}
}

You can then add a custom image stamp by adding the picture into a new AnnBatesStamp. Here is an example on how you can add this stamp:

private void AddStamp(RasterImage image)
{
using (AnnBatesStampComposer batesStampComposer = new AnnBatesStampComposer())
{
AnnBatesStampComposer.RenderingEngine = new AnnWinFormsRenderingEngine();
AnnContainer batesStampContainer = new AnnContainer();
batesStampContainer.Mapper.MapResolutions(image.XResolution, image.YResolution, image.XResolution, image.YResolution);
batesStampContainer.Size = batesStampContainer.Mapper.SizeToContainerCoordinates(LeadSizeD.Create(image.Width, image.Height));
using (AnnBatesStamp batesStamp = new AnnBatesStamp())
{
batesStamp.HorizontalAlignment = AnnHorizontalAlignment.Left;
batesStamp.VerticalAlignment = AnnVerticalAlignment.Top;
string imageFile = “@C:\watermarks\input.png”; // logo image to add
batesStamp.Logo.Picture = new AnnPicture(imageFile);
batesStampComposer.Stamps.Add(batesStamp);
batesStampComposer.TargetContainers.Add(batesStampContainer);
RasterImage watermarkedImage = null;
watermarkedImage = AnnBatesStampComposer.RenderingEngine.RenderOnImage(batesStampContainer, image).Clone();
for (int i = 1; i <= image.PageCount; i++)
{
image.Page = i;
if (watermarkedImage == null)
watermarkedImage = AnnBatesStampComposer.RenderingEngine.RenderOnImage(batesStampContainer, image).Clone();
else
watermarkedImage.AddPage(AnnBatesStampComposer.RenderingEngine.RenderOnImage(batesStampContainer, image).Clone());
}
return watermarkedImage; // RasterImage which contains the stamp that can be loaded in the viewer
}
}
}

https://www.leadtools.com/help/sdk/v22/tutorials/dotnet-winforms-display-files-in-the-document-viewer.html

https://www.leadtools.com/help/sdk/v22/dh/abs/annbatesstampcomposer.html

2 Replies

Know the answer? Post it — somebody with the same question will find it here.

Rajesh Gami4y ago
Check the below link, I hope it works for you

https://ej2.syncfusion.com/angular/documentation/pdfviewer/annotation/stamp-annotation/
Marvin Reid4y ago
You can load the base64 string using the LEADDocument class, and then display the PDF using the DocumentViewer class which is showed in the documentation below. Here is how you can first handle the loading of the PDF from Base64:
static LEADDocument LEADDocumentFrom64(string b64Str)
{
   byte[] bytes = Convert.FromBase64String(b64Str);
   using (MemoryStream ms = new MemoryStream(bytes))
   {
      return DocumentFactory.LoadFromStream(ms, new LoadDocumentOptions());
   }
}
You can then add a custom image stamp by adding the picture into a new AnnBatesStamp. Here is an example on how you can add this stamp:
private void AddStamp(RasterImage image)
{
   using (AnnBatesStampComposer batesStampComposer = new AnnBatesStampComposer())
   {
      AnnBatesStampComposer.RenderingEngine = new AnnWinFormsRenderingEngine();
      AnnContainer batesStampContainer = new AnnContainer();
      batesStampContainer.Mapper.MapResolutions(image.XResolution, image.YResolution, image.XResolution, image.YResolution);
      batesStampContainer.Size = batesStampContainer.Mapper.SizeToContainerCoordinates(LeadSizeD.Create(image.Width, image.Height));

      using (AnnBatesStamp batesStamp = new AnnBatesStamp())
      {
         batesStamp.HorizontalAlignment = AnnHorizontalAlignment.Left;
         batesStamp.VerticalAlignment = AnnVerticalAlignment.Top;

         string imageFile = “@C:\watermarks\input.png”; // logo image to add
         batesStamp.Logo.Picture = new AnnPicture(imageFile);
         batesStampComposer.Stamps.Add(batesStamp);
         batesStampComposer.TargetContainers.Add(batesStampContainer);

         RasterImage watermarkedImage = null;
         watermarkedImage = AnnBatesStampComposer.RenderingEngine.RenderOnImage(batesStampContainer, image).Clone();

         for (int i = 1; i <= image.PageCount; i++)
         {
            image.Page = i;
            if (watermarkedImage == null)
               watermarkedImage = AnnBatesStampComposer.RenderingEngine.RenderOnImage(batesStampContainer, image).Clone();
            else
               watermarkedImage.AddPage(AnnBatesStampComposer.RenderingEngine.RenderOnImage(batesStampContainer, image).Clone());
         }
         return watermarkedImage; // RasterImage which contains the stamp that can be loaded in the viewer

      }
   }
}
https://www.leadtools.com/help/sdk/v22/tutorials/dotnet-winforms-display-files-in-the-document-viewer.html
https://www.leadtools.com/help/sdk/v22/dh/abs/annbatesstampcomposer.html