Added pagecount property

Author: ff-gerard

src/Synercoding.FileFormats.Pdf/LowLevel/PageTree.cs

@@ -1,5 +1,4 @@
 using Synercoding.FileFormats.Pdf.LowLevel.Extensions;
-using Synercoding.FileFormats.Pdf.LowLevel.Text;
 using Synercoding.FileFormats.Pdf.LowLevel.XRef;
 using System;
 using System.Collections.Generic;
@@ -25,6 +24,9 @@ public PageTree(PdfReference id, TableBuilder tableBuilder)
         public void AddPage(PdfPage pdfObject)
             => _pages.Add(pdfObject);
 
+        public int PageCount
+            => _pages.Count;
+
         internal uint WriteToStream(PdfStream stream)
         {
             if (_isWritten)

src/Synercoding.FileFormats.Pdf/PdfWriter.cs

@@ -54,6 +54,12 @@ public PdfWriter(Stream stream, bool ownsStream)
         /// </summary>
         public DocumentInformation DocumentInformation { get; }
 
+        /// <summary>
+        /// Returns the number of pages already added to the writer
+        /// </summary>
+        public int PageCount
+            => _pageTree.PageCount;
+
         /// <summary>
         /// Set meta information for this document
         /// </summary>