// Install IronPdf with Nuget:  PM> Install-Package IronPdf
using IronPdf;
using System.Collections.Generic;

var Renderer = new IronPdf.HtmlToPdf();

// Join Multiple Existing PDFs into a single document
var PDFs     = new List<PdfDocument>();
PDFs.Add(PdfDocument.FromFile("A.pdf"));
PDFs.Add(PdfDocument.FromFile("B.pdf"));
PDFs.Add(PdfDocument.FromFile("C.pdf"));
PdfDocument PDF =  PdfDocument.Merge(PDFs);
PDF.SaveAs("merged.pdf");

// Add a cover page
PDF.PrependPdf(Renderer.RenderHtmlAsPdf("<h1>Cover Page</h1><hr>"));

// Remove the last page from the PDF and save again
PDF.RemovePage(PDF.PageCount - 1);
PDF.SaveAs("merged.pdf");

// Copy pages 5-7 and save them as a new document.
PDF.CopyPages(4,6).SaveAs("exerpt.pdf");

' Install IronPdf with Nuget:  PM> Install-Package IronPdf
Imports IronPdf
Imports System.Collections.Generic

Private Renderer = New IronPdf.HtmlToPdf()

' Join Multiple Existing PDFs into a single document
Private PDFs = New List(Of PdfDocument)()
PDFs.Add(PdfDocument.FromFile("A.pdf"))
PDFs.Add(PdfDocument.FromFile("B.pdf"))
PDFs.Add(PdfDocument.FromFile("C.pdf"))
Dim PDF As PdfDocument = PdfDocument.Merge(PDFs)
PDF.SaveAs("merged.pdf")

' Add a cover page
PDF.PrependPdf(Renderer.RenderHtmlAsPdf("<h1>Cover Page</h1><hr>"))

' Remove the last page from the PDF and save again
PDF.RemovePage(PDF.PageCount - 1)
PDF.SaveAs("merged.pdf")

' Copy pages 5-7 and save them as a new document.
PDF.CopyPages(4,6).SaveAs("exerpt.pdf")