C#/VB.NET : ajouter des numéros de page à des documents PDF existants

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.AutomaticFields;
    using Spire.Pdf.Graphics;
    using System.Drawing;
    
    
    namespace AddPageNumbers
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Load a PDF document
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile("Sample.pdf");
    
                //Create a true type font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 10f, FontStyle.Regular), true);
    
                //Create a PdfPageNumberField instance
                PdfPageNumberField pageNumber = new PdfPageNumberField();
    
                //Create a PdfPageCountField instance
                PdfPageCountField pageCount = new PdfPageCountField();
    
                //Create a PdfCompositeField instance
                PdfCompositeField compositeField = new PdfCompositeField(font, PdfBrushes.Black, "Page {0} of {1}", pageNumber, pageCount);
                //Set the text alignment for the composite field
                compositeField.StringFormat = new PdfStringFormat(PdfTextAlignment.Left, PdfVerticalAlignment.Top);
    
                //Loop through the pages
                for(int i = 0; i < pdf.Pages.Count; i ++)
                {
                    //Draw composite filed on each page
                    compositeField.Draw(pdf.Pages[i].Canvas, pdf.Pages[i].Size.Width / 2 - 20, pdf.Pages[i].Size.Height - pdf.PageSettings.Margins.Bottom);
                }
    
                //Save the result document
                pdf.SaveToFile("AddPageNumbers.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.AutomaticFields
    Imports Spire.Pdf.Graphics
    
    Namespace AddPageNumbers
        Friend Class Program
            Private Shared Sub Main(ByVal args As String())
                'Load a PDF document
                Dim pdf As PdfDocument = New PdfDocument()
                pdf.LoadFromFile("Sample.pdf")
    
                'Create a true type font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 10F, FontStyle.Regular), True)
    
                'Create a PdfPageNumberField instance
                Dim pageNumber As PdfPageNumberField = New PdfPageNumberField()
    
                'Create a PdfPageCountField instance
                Dim pageCount As PdfPageCountField = New PdfPageCountField()
    
                'Create a PdfCompositeField instance
                Dim compositeField As PdfCompositeField = New PdfCompositeField(font, PdfBrushes.Black, "Page {0} of {1}", pageNumber, pageCount)
                'Set the text alignment for the composite field
                compositeField.StringFormat = New PdfStringFormat(PdfTextAlignment.Left, PdfVerticalAlignment.Top)
    
                'Loop through the pages
                For i As Integer = 0 To pdf.Pages.Count - 1
                    'Draw composite filed on each page
                    compositeField.Draw(pdf.Pages(i).Canvas, pdf.Pages(i).Size.Width / 2 - 20, pdf.Pages(i).Size.Height - pdf.PageSettings.Margins.Bottom)
                Next
    
                'Save the result document
                pdf.SaveToFile("AddPageNumbers.pdf")
            End Sub
        End Class
    End Namespace