API .NET de código aberto para processamento de PDF

Comando NuGet

 Install-Package PdfSharp

Com o Visual Studio, você pode instalar o Gerenciador de Pacotes NuGet para acessar facilmente os pacotes NuGet. Funciona com o VS 2012 Express, bem como com as edições da comunidade do VS 2013 e VS 2015. No Visual Studio vá para "Ferramentas" => "Extensões e Atualizações..." para instalar o Gerenciador de Pacotes NuGet, caso ainda não o tenha. O Gerenciador de Pacotes NuGet baixará o pacote para você, o instalará e adicionará uma referência ao seu projeto.

Criar PDF usando C#

// Create a new PDF document
PdfDocument pdfDocument = new PdfDocument();
// Create an empty page
PdfPage pdfPage = pdfDocument.AddPage();
// Get an XGraphics object for drawing
XGraphics xGraphics = XGraphics.FromPdfPage(pdfPage);
// Create a font
XFont xFont = new XFont("Verdana", 20, XFontStyle.BoldItalic);
// Draw the text
xGraphics.DrawString("File Format Developer Guide", xFont, XBrushes.Black,
    new XRect(0, 0, pdfPage.Width, pdfPage.Height),
    XStringFormats.Center);
// Save the document...
pdfDocument.Save("fileformat.pdf");
    

Criar uma anotação de texto PDF via C#

 // Create a PDF text annotation
PdfTextAnnotation textAnnot = new PdfTextAnnotation();
textAnnot.Title = "This is the title";
textAnnot.Subject = "This is the subject";
textAnnot.Contents = "This is the contents of the annotation.\rThis is the 2nd line.";
textAnnot.Icon = PdfTextAnnotationIcon.Note;
gfx.DrawString("The first text annotation", font, XBrushes.Black, 30, 50, XStringFormats.Default);
// Convert rectangle from world space to page space. This is necessary because the annotation is
// placed relative to the bottom left corner of the page with units measured in point.
XRect rect = gfx.Transformer.WorldToDefaultPage(new XRect(new XPoint(30, 60), new XSize(30, 30)));
textAnnot.Rectangle = new PdfRectangle(rect);
// Add the annotation to the page
page.Annotations.Add(textAnnot);

Combinar documentos via Java

 // Open the input files
PdfDocument inputDocument1 = PdfReader.Open(filename1, PdfDocumentOpenMode.Import);
PdfDocument inputDocument2 = PdfReader.Open(filename2, PdfDocumentOpenMode.Import);
// Create the output document
PdfDocument outputDocument = new PdfDocument();
// Show consecutive pages facing. Requires Acrobat 5 or higher.
outputDocument.PageLayout = PdfPageLayout.TwoColumnLeft;
XFont font = new XFont("Verdana", 10, XFontStyle.Bold);
XStringFormat format = new XStringFormat();
format.Alignment = XStringAlignment.Center;
format.LineAlignment = XLineAlignment.Far;
XGraphics gfx;
XRect box;
int count = Math.Max(inputDocument1.PageCount, inputDocument2.PageCount);
for (int idx = 0; idx < count; idx++)
{
// Get page from 1st document
PdfPage page1 = inputDocument1.PageCount > idx ?
inputDocument1.Pages[idx] : new PdfPage();
// Get page from 2nd document
PdfPage page2 = inputDocument2.PageCount > idx ?
inputDocument2.Pages[idx] : new PdfPage();
// Add both pages to the output document
page1 = outputDocument.AddPage(page1);
page2 = outputDocument.AddPage(page2);
// Write document file name and page number on each page
gfx = XGraphics.FromPdfPage(page1);
box = page1.MediaBox.ToXRect();
box.Inflate(0, -10);
gfx.DrawString(String.Format("{0} • {1}", filename1, idx + 1),
font, XBrushes.Red, box, format);
gfx = XGraphics.FromPdfPage(page2);
box = page2.MediaBox.ToXRect();
box.Inflate(0, -10);
gfx.DrawString(String.Format("{0} • {1}", filename2, idx + 1),
font, XBrushes.Red, box, format);
}
// Save the document...
const string filename = "CompareDocument1_tempfile.pdf";
outputDocument.Save(filename);