title: Reorder pages in a pdf file using itextsharp
body: <p>I'm trying to reorder several pages in a PDF file. I found some code in a blog but couldn't get it to work. I have a two page pdf, and I want to get the last page to appear as first. I always get an exception saying that page number has to match with order. When I checked the document object, it shows 0 pages. But the PDF passed into has two pages.</p>
  
  <pre><code>public void reOrder(string inputFile)
  { 
      Document document = new Document();
      FileStream fs = new FileStream(inputFile, FileMode.Open);
      PdfWriter writer = PdfWriter.GetInstance(document, fs);
      document.AddDocListener(writer);                
      writer.SetLinearPageMode();
      int[] order = {2,1};
      writer.ReorderPages(order);
  }
  </code></pre>