public static byte[] MergePdfFiles(List <byte[]> pdfFileBytesList, PdfResizeInfo pageSizeInfo, PdfScalingOptions scalingOptions = null)
{
if (pdfFileBytesList == null || !pdfFileBytesList.Any())
{
throw new ArgumentNullException(nameof(pdfFileBytesList), "List of Pdf Files to be merged cannot be null or empty.");
}
if (pageSizeInfo == null)
{
throw new ArgumentNullException(nameof(pageSizeInfo), "ResizeInfo cannot be null.");
}
byte[] outputBytes = null;
//NOTE: For Merging we DISABLE ALL SCALING by default, so that we can preserve Annotations, etc.
// but this can be easily set by the client code to enable scaling.
var pdfScalingOptions = scalingOptions ?? PdfScalingOptions.DisableScaling;
//Set static references for Pdf Processing...
PdfReader.unethicalreading = pdfScalingOptions.EnableUnethicalReading;
Document.Compress = pdfScalingOptions.EnableCompression;
var targetPageSize = pageSizeInfo.PageSize;
var targetMarginSize = pageSizeInfo.MarginSize;
using (var outputMemoryStream = new MemoryStream())
using (var pdfDocBuilder = new Document(targetPageSize, targetMarginSize.Left, targetMarginSize.Right, targetMarginSize.Top, targetMarginSize.Bottom))
using (var pdfSmartCopy = new PdfSmartCopy(pdfDocBuilder, outputMemoryStream))
{
pdfDocBuilder.Open();
foreach (var pdfBytes in pdfFileBytesList)
{
if (pdfScalingOptions.EnableScaling)
{
var scaledPdfBytes = PdfResizeHelper.ResizePdfPageSize(pdfBytes, pageSizeInfo, pdfScalingOptions);
pdfSmartCopy.AppendPdfDocument(scaledPdfBytes);
}
else
{
pdfSmartCopy.AppendPdfDocument(pdfBytes);
}
}
pdfDocBuilder.Close();
outputBytes = outputMemoryStream.ToArray();
}
return(outputBytes);
}