> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/core/get-started/samples/pdfviewform.md).

# PDF Viewer Component in C#, VB- PDFView

Sample C#, VB code for using Apryse SDK's PDF viewer control to implement a number of custom tools (such as freehand tool, link creation tool, rectangular zoom etc) and custom GUI elements (such as cu

Sample C#, VB (.NET) code for using Apryse SDK's PDF viewer control to implement a number of custom tools (such as freehand tool, link creation tool, rectangular zoom etc) and custom GUI elements (such as custom navigation and printing).

For a more introductory example of how to use PDFViewCtrl, please take a look at the [PDFViewSimple sample code](/core/get-started/samples/pdfviewsimpletest.md).

Learn more about our [Server SDK for .NET](/core/get-started/frameworks/dotnet.md) and [PDF Viewer SDK](/core/viewer/viewer.md).

{% tabs %}
{% tab title="C#" %}
{% code lineNumbers="true" %}

```csharp
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Printing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;

using pdftron;
using pdftron.PDF;
using pdftron.SDF;
using pdftron.Common;

namespace PDFViewCS
{

   /// <summary>
   /// Summary description for PDFViewForm.
   /// </summary>
   public class PDFViewForm : System.Windows.Forms.Form
   {

      /// <summary>
      /// Required designer variable.
      /// </summary>
      private System.ComponentModel.Container components = null;

#if CUSTOM_NAV

      // The following variables are used for custom page navigation pane...
      private System.Windows.Forms.TabControl _pdfdoc_tab;
      private System.Windows.Forms.TabPage _bookmarks_tab;
      private System.Windows.Forms.TabPage _pages_tab;
      private System.Windows.Forms.TabPage _layers_tab;
      private System.Windows.Forms.TreeView bookmark_tree;
      private System.Windows.Forms.TreeView layer_tree;
      private System.Windows.Forms.Splitter splitter1;
      private ThumbView _thumbview = null;  // Custom thumbnail view.

#endif

      private PDFDoc _pdfdoc = null;        // Currently open PDF document.
      private MyPDFView _pdfview = null;    // Main PDF view.
      public PDFViewForm(MainForm main_form)
      {
         this.MdiParent = main_form;

         // Create other controls created using Windows Form Designer
         InitializeComponent();

         // Create the main PDFViewCtrl control (we do it here manually for greater control)
         _pdfview = new MyPDFView(this);
         _pdfview.Location = new System.Drawing.Point(0, 0);
         _pdfview.Dock = System.Windows.Forms.DockStyle.Fill;

         // Optional: Set the error and current page delegates...
         _pdfview.SetErrorReportHandler(new PDFViewErrorDelegate(ErrorMsg), null);
         _pdfview.SetCurrentPageHandler(new PDFViewCurrentPageDelegate(UpdateStatusBar), main_form);
         _pdfview.SetDownloadReportHandler(new PDFViewDownloadDelegate(OnDownload), null);
         _pdfview.SetUrlExtraction(false);
         Controls.Add(_pdfview);
      }

      public bool OpenPDF(String filename)
      {
         try
         {
            try
            { 
               // Try to open as a PDF document...
               _pdfdoc = new PDFDoc(filename);
            }
            catch (Exception ex)
            {
               // Try to open as a PNG, JPEG, TIF, BMP, GIF, etc.
               _pdfdoc = OpenImage(filename);
               if (_pdfdoc == null)
               {
                  throw ex; // re-throw the original exception
               }
            }

            if (!_pdfdoc.InitSecurityHandler())  // In case _pdfdoc is encrypted
            {
               MessageBox.Show("Document authentication error", "PDFViewCtrl Error");
               return false;
            }

#if CUSTOM_NAV

            // Populates a custom bookmark tree control with bookmark nodes (if any). 
            Bookmark root = _pdfdoc.GetFirstBookmark();
            if (root.IsValid()) 
            {
               bookmark_tree.BeginUpdate();
               BuildBookmarkTree(root, bookmark_tree.Nodes);
               bookmark_tree.EndUpdate();
            }

            else 
            {  
               // Optional: Uncomment the following line to hide the bookmark 
               // tab if the document does not containing bookmarks?:
               // _pdfdoc_tab.Hide();
            }

            // Add OCGs (if any) to 'PDF Layers' tab.
            if (_pdfdoc.HasOC()) 
            {
               pdftron.PDF.OCG.Config cfg = _pdfdoc.GetOCGConfig();
               Obj order = cfg.GetOrder();
               if (order != null) {
                  layer_tree.BeginUpdate();
                  BuildLayerTree(order, cfg, layer_tree.Nodes, null);
                  layer_tree.EndUpdate();
               }
            }

#endif

            // Optional: Set page view and page presentation mode.
            // _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_page);
            // _pdfview.SetPageViewMode(PDFViewCtrl.PageViewMode.e_fit_page);
            // _pdfview.SetProgressiveRendering(false);

            if (_pdfdoc.GetPageCount() > 2000)
            {
               // If the document has many pages use single page mode to seed up initial rendering.
               _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_page);
            }

            _pdfview.SetDoc(_pdfdoc);

#if CUSTOM_NAV

            _thumbview.SetDoc(_pdfdoc, _pdfview);

#endif

            SetToolMode(MyPDFView._base_tool_mode, MyPDFView._tool_mode); // Set the view to use the currently selected tool (i.e. hand, text selection, pencil, etc).
         }
         catch (PDFNetException ex)
         {
            MessageBox.Show(ex.Message);
            return false;
         }
         catch (Exception ex)
         {
            MessageBox.Show(ex.ToString());
            return false;
         }

         this.Text = filename;  // Set the title

         return true;
      }

      public bool OpenPDFUrl(String url, String password)
      {
         try
         {
            // Open a PDF file at the given url. This works best with PDF's that
            // are linearized, as pages can be downloaded and viewed in random access order,
            // without the need to download the entire document. A viewing session can also be
            // persisted across multiple viewing/application sessions to remove redundant downloads 
            // and improve overall performance by using the optional cache_file parameter.
            _pdfview.OpenURLAsync(url, "", password);
         }
         catch (PDFNetException ex)
         {
            MessageBox.Show(ex.Message);
            return false;
         }
         catch (Exception ex)
         {
            MessageBox.Show(ex.ToString());
            return false;
         }

         this.Text = url;  // Set the title
         return true;
      }

      /// <summary>
      ///  This callback method (delegate) was registered using _pdfview.SetDownloadReportHandler 
      ///  in PDFViewCS constructor. The callback can be used to update download progress
      ///  within GUI applications etc.
      /// </summary>
      private void OnDownload(DownloadedType type, Int32 page_num, Int32 obj_num, String msg, Object obj)
      {
         switch (type)
         {
            case DownloadedType.e_opened:
               // e_opened indicates that we have a valid, but incomplete PDFDoc.
               _pdfdoc = _pdfview.GetDoc();
               MainForm main_form = (MainForm)this.MdiParent;
               main_form.UpdateStatusBar(_pdfview.GetCurrentPage(), _pdfview.GetDoc().GetPageCount());
               // the PDF should be treated as read only, and only simple functions
               // should be called on the doc, until e_finished has been called.
               break;
            case DownloadedType.e_page:
               // this indicates the entire page is downloaded and it is safe to modify.
               // for example add a new annotation
               break;
            case DownloadedType.e_finished:
               // we now have the full PDF file and it can be treated like any other
               if (MessageBox.Show("Download complete, would you like to save the PDF locally?", "PDF Downloaded", MessageBoxButtons.YesNo) == DialogResult.Yes)
               {
                  SaveAs();
               }
               break;
            case DownloadedType.e_failed:

               // downloading has stopped if this occurs
               MessageBox.Show(msg);
               this.Text = "";
               break;
         }
      }

      // A utility function used to display other images types besides PDF 
      // inside MyPDFView. This functionality can be used to display TIF, JPEG, 
      // BMP, PNG, etc.
      public PDFDoc OpenImage(string filename)
      {
         try
         {
            PDFDoc pdfDoc = new PDFDoc();  // create new document 
            ElementBuilder f = new ElementBuilder();
            ElementWriter writer = new ElementWriter();
            Page page = pdfDoc.PageCreate(); // Add a blank page 
            writer.Begin(page);

            // Add image to the document. 
            pdftron.PDF.Image img = pdftron.PDF.Image.Create(pdfDoc, filename);

            // get image rectangle 
            Rect imgBox = new Rect(0, 0, img.GetImageWidth(),
            img.GetImageHeight());
            Rect scaledBox = new Rect();
            double scaleFactor;

            if (imgBox.Height() / imgBox.Width() > 792 / 612)
            {
               scaleFactor = imgBox.Height() / 792;
            }
            else
            {
               scaleFactor = imgBox.Width() / 612;
            }
            scaledBox.x2 = imgBox.x2 / scaleFactor;
            scaledBox.y2 = imgBox.y2 / scaleFactor;

            // set crop and media box of this page to fit with the scaled image 
            page.SetCropBox(scaledBox);
            page.SetMediaBox(scaledBox);

            // create the image element and add it to the page 
            int width = (int)scaledBox.Width();
            int height = (int)scaledBox.Height();
            int offsetX = 0;
            int offsetY = 0;

            Element element = f.CreateImage(img, new Matrix2D(width, 0, 0, height, offsetX, offsetY));
            writer.WritePlacedElement(element);
            writer.End(); // Finish writing to the page 
            pdfDoc.PagePushBack(page);

            return pdfDoc;
         }
         catch (Exception)
         {
            // MessageBox.Show(ex.ToString()); 
            return null;
         }
      }

      public Boolean IsNavSidebarVisible()
      {
         return _pdfview.IsNavPanelVisible();
      }
      public void ShowNavSidebar(Boolean show)
      {
         _pdfview.ShowNavPanel(show);
      }
      public PDFDoc GetPDFDoc()
      {
         if (_pdfview == null) return null;
         else return _pdfview.GetDoc();
      }
      public void FitPage()
      {
         _pdfview.SetPageViewMode(PDFViewCtrl.PageViewMode.e_fit_page);
      }

      public void FitWidth()
      {
         _pdfview.SetPageViewMode(PDFViewCtrl.PageViewMode.e_fit_width);
      }

      public void ZoomIn()
      {
         _pdfview.SetZoom(_pdfview.GetZoom() * 2);
      }

      public void ZoomOut()
      {
         _pdfview.SetZoom(_pdfview.GetZoom() / 2);
      }
      public void FirstPage()
      {
         _pdfview.GotoFirstPage();
      }
      public void PrevPage()
      {
         _pdfview.GotoPreviousPage();
      }

      public void NextPage()
      {
         _pdfview.GotoNextPage();
      }
      public void LastPage()
      {
         _pdfview.GotoLastPage();
      }

      public void PageSingle()
      {
         _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_page);
      }
      public void PageSingleContinuous()
      {
         _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_continuous);
      }
      public void PageFacingContinuous()
      {
         _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_facing_continuous);
      }

      public void PageFacing()
      {
         _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_facing);
      }

      public void RotateClockwise()
      {
         _pdfview.RotateClockwise();
      }

      public void RotateCounterClockwise()
      {
         _pdfview.RotateCounterClockwise();
      }

      public void DocProperties()
      {
         _pdfview.DocProperties();
      }

      public void DeletePages()
      {
         _pdfview.DeletePages();
      }

      public void InsertBlankPages()
      {
         _pdfview.InsertBlankPages();
      }

      public void InsertPages()
      {
         _pdfview.InsertPages();
      }

      public void ReplacePages()
      {
         _pdfview.ReplacePages();
      }

      public void SetAntiAliasing(bool anti_alias)
      {
         _pdfview.SetAntiAliasing(anti_alias);
         _pdfview.Update();
      }
      public void SetRasterizer(bool built_in)
      {
         if (built_in)
            _pdfview.SetRasterizerType(PDFRasterizer.Type.e_BuiltIn);
         else
            _pdfview.SetRasterizerType(PDFRasterizer.Type.e_GDIPlus);

         _pdfview.Update();
      }

      public void SetSmoothImages(bool smooth_images)
      {
         _pdfview.SetImageSmoothing(smooth_images);
         _pdfview.Update();
      }



      public void Save(string filename)
      {
         if (_pdfdoc == null) return;

         _pdfdoc.Lock();

         try
         {
            // If the user created new markup, merge it before saving the document.
            if (_pdfview != null)
            {
               if (_pdfview._freehand_markup != null)
               {
                  foreach (DictionaryEntry itr in _pdfview._freehand_markup)
                  {
                     int annot_page_num = (int)itr.Key;
                     Page pg = _pdfdoc.GetPage(annot_page_num);

                     if (pg != null)
                     {
                        FreeHandAnnot annot = (FreeHandAnnot)itr.Value;
                        annot.DrawAnnots(pg, Pens.Red);
                     }
                  }

                  _pdfview._freehand_markup = null;
                  _pdfview.Invalidate();
                  _pdfview.Update();
               }
            }

            _pdfdoc.Save(filename, pdftron.SDF.SDFDoc.SaveOptions.e_remove_unused);
         }
         catch (Exception ex)
         {
            MessageBox.Show(ex.ToString(), "Error during the Save");
         }

         _pdfdoc.Unlock();
      }

      public void SaveAs()
      {
         // Check if there are any annotations that need to 
         // be merged with the document.
         if (_pdfdoc != null && _pdfview != null)
         {
            SaveFileDialog dlg = new SaveFileDialog();
            dlg.Filter = "PDF Files (*.pdf)|*.pdf|All Files (*.*)|*.*";
            dlg.DefaultExt = ".pdf";
            dlg.FileName = Text;
            DialogResult res = dlg.ShowDialog();

            if (res == DialogResult.OK)
            {
               this.Save(dlg.FileName);
            }
         }
      }

      protected override void OnClosing(CancelEventArgs e)
      {
         // Check if there are any annotations that need to 
         // be merged with the document.
         if (_pdfdoc != null && _pdfview != null && (_pdfdoc.IsModified() || _pdfview._freehand_markup != null))
         {
            DialogResult save = MessageBox.Show("Would you like to save the changes to the document?", "PDFViewCtrl", MessageBoxButtons.YesNoCancel);

            if (save == DialogResult.Yes)
            {
               SaveFileDialog dlg = new SaveFileDialog();
               dlg.Filter = "PDF Files (*.pdf)|*.pdf|All Files (*.*)|*.*";
               dlg.DefaultExt = ".pdf";
               dlg.FileName = Text;
               DialogResult res = dlg.ShowDialog();

               if (res == DialogResult.OK)
               {
                  this.Save(dlg.FileName);
               }
               else if (res == DialogResult.Cancel)
               {
                  e.Cancel = true;
               }
            }
            else if (save == DialogResult.Cancel)
            {
               e.Cancel = true;
            }
            base.OnClosing(e);
         }
      }

      /// <summary>
      /// Clean up any resources being used.
      /// </summary>
      protected override void Dispose(bool disposing)
      {
         if (disposing)
         {

#if CUSTOM_NAV

            _thumbview.Dispose(); // Close the thumbnail view.

#endif

            if (_pdfview != null)
            {
               _pdfview.CloseDoc();
               _pdfview.Dispose();   // Close the open PDF document in the view.
            }

            if (_pdfdoc != null)
            {
               _pdfdoc.Dispose();    // Close the PDF document.
            }

            if (components != null)
            {
               components.Dispose();
            }
         }

         base.Dispose(disposing);
      }

      /// <summary>
      ///  This callback method (delegate) was registered using _pdfview.SetErrorReportProc 
      ///  in PDFViewCS constructor. The callback can be used to report any errors that may 
      ///  occur during page rendering.
      /// </summary>
      public static void ErrorMsg(String message, Object obj)
      {
         MessageBox.Show(message, "PDFViewCtrl Error");
      }

#if CUSTOM_NAV // Custom bookmark and PDF layer navigation sample

      // Handle the the bookmark select event (i.e. when the user selects a node in the bookmark tree).
      private void BookmarkTreeAfterSelect(System.Object sender, System.Windows.Forms.TreeViewEventArgs e)
      {
         if (e.Node.Tag == null) return;

         _pdfdoc.Lock();
         Bookmark item = (Bookmark) e.Node.Tag;
         Action action = item.GetAction();

         if (action.IsValid())  // Handle goto actions. 
         {
            // Other types of actions can be handled in similar way.
            if (action.GetType() == Action.Type.e_GoTo)
            {
               Destination dest = action.GetDest();
               if (dest.IsValid()) 
               {
                  Page page = dest.GetPage();
                  if (page != null)	_pdfview.SetCurrentPage(page.GetIndex());
               }
            }
         }
         _pdfdoc.Unlock();
      }

      // Populate the bookmark tree control with bookmark items.
      static void BuildBookmarkTree(Bookmark item, TreeNodeCollection nodes)
      {
         for (int i=0; item.IsValid(); item=item.GetNext(), ++i)
         {
            TreeNode new_node = new TreeNode(item.GetTitle());
            nodes.Add(new_node);
            new_node.Tag = item;
            if (item.IsOpen()) new_node.Expand();

            if (item.HasChildren())	 // Recursively add children sub-trees
            {
               BuildBookmarkTree(item.GetFirstChild(), new_node.Nodes);
            }
         }
      }

      // Handle the the layer On/OFF event
      private void LayerTreeAfterCheck(object sender, System.Windows.Forms.TreeViewEventArgs e)
      {
         pdftron.PDF.OCG.Context ctx = _pdfview.GetOCGContext();
         if (ctx == null || e.Node.Tag == null) return;

         pdftron.PDF.OCG.Group ocg = (pdftron.PDF.OCG.Group) e.Node.Tag;
         ctx.SetState(ocg, e.Node.Checked);
         _pdfview.Update();
      }

      // Populate the layer tree control with OCG (Optional Content Group) layers.
      static void BuildLayerTree(Obj layer_arr, pdftron.PDF.OCG.Config init_cfg, TreeNodeCollection nodes, TreeNode parent_node)
      {
         if (layer_arr == null || layer_arr.IsArray() == false) return;

         Obj lobj;
         int sz = layer_arr.Size();
         for (int i=0; i<sz; ++i)
         {
            lobj = layer_arr.GetAt(i);
            if (lobj.IsArray() && lobj.Size()>0) 
            {
               TreeNode new_node = new TreeNode();					
               nodes.Add(new_node);
               new_node.Checked = true;
               new_node.Expand();

               // Recursively add children sub-trees
               BuildLayerTree(lobj, init_cfg, new_node.Nodes, new_node);

            }
            else if (i==0 && lobj.IsString()) 
            {
               parent_node.Text = lobj.GetAsPDFText();
            }
            else 
            {
               pdftron.PDF.OCG.Group grp = new pdftron.PDF.OCG.Group(lobj);
               if (grp.IsValid()) 
               {
                  TreeNode new_node = new TreeNode(grp.GetName());
                  nodes.Add(new_node);
                  new_node.Tag = grp;
                  new_node.Checked = grp.GetInitialState(init_cfg);
               }
            }
         }
      }

#endif

      /// <summary>
      ///  This callback method (delegate) was registered using _pdfview.SetCurrentPageProc 
      ///  in PDFViewCS constructor. The callback can be used to update the current page number
      ///  within GUI applications etc. In this case we update the status bar in the main form.
      /// </summary>
      public static void UpdateStatusBar(int current_page, int num_pages, Object data)
      {
         if (data != null)
         {
            MainForm main_form = (MainForm)data;
            main_form.UpdateStatusBar(current_page, num_pages);
         }
      }

      protected override void OnActivated(EventArgs e)
      {
         if (_pdfview != null && _pdfview.GetDoc() != null)
         {
            MainForm main_form = (MainForm)this.MdiParent;
            main_form.UpdateStatusBar(_pdfview.GetCurrentPage(), _pdfview.GetDoc().GetPageCount());
         }
      }

      public void SetToolMode(PDFViewCtrl.ToolMode tool_mode, MyPDFView.CustomToolMode custom_tool_mode)
      {
         MyPDFView._base_tool_mode = tool_mode;
         MyPDFView._tool_mode = custom_tool_mode;
         _pdfview.SetToolMode(tool_mode);
      }

      public void Export()
      {
         ExportDialog e = new ExportDialog(this._pdfdoc);
         e.ShowDialog();
      }

      public void CopySelectedText()
      {
         _pdfview.OnTextCopy(null, null);
      }

      public void SelectAll()
      {
         _pdfview.SelectAll();
      }

      public void DeselectAll()
      {
         _pdfview.ClearSelection();
      }

      public void FindText()
      {
         _pdfview.Find(); // Use the build in Find text dialog.
      }
      public void Print()
      {
         try
         {

#if CUSTOM_PRINT

            PrintDialog print_dlg = new PrintDialog();
            print_dlg.AllowSomePages = true;
            print_dlg.Document = _print_doc;
            if (print_dlg.ShowDialog() == DialogResult.OK) 
            {
               _pdfdraw = new PDFDraw();
               _pdfdraw.SetPrintMode(true);
               _print_doc.Print();
               _pdfdraw.Dispose(); 
               _pdfdraw = null;
            }

#else

            _pdfview.Print(); // Use built in PDFPrint function.

#endif     

         }
         catch (Exception ex)
         {
            MessageBox.Show(ex.ToString());
         }
      }

#if CUSTOM_PRINT

      // In this sample, PDFDraw object is used to implement print support.
      private PDFDraw _pdfdraw = null;
      private PageIterator print_page_itr;
      private System.Drawing.Printing.PrintDocument _print_doc;

      private void OnBeginPDFPrint(object sender, PrintEventArgs ev)
      {
         PDFDoc pdfdoc = GetPDFDoc();
         if (pdfdoc == null) 
         {
            MessageBox.Show("Error: Print document is not selected.");
            return;
         }

         print_page_itr = pdfdoc.GetPageIterator();

         // PDFNet includes two different rasterizer implementations. 
         //
         // The two implementations offer a trade-off between print
         // speed and accuracy/quality, as well as a trade-off between 
         // vector and raster output.
         //
         // e_GDIPlus rasterizer can be used to render the page 
         // using Windows GDI+, whereas e_BuiltIn rasterizer can
         // be used to render bitmaps using platform-independent 
         // graphics engine (in this case images are always converted 
         // to bitmap prior to printing).
         _pdfdraw.SetRasterizerType(PDFRasterizer.Type.e_GDIPlus);

         // You can uncomment the following lines in order to use 
         // built-in, platform-independent rasterizer instead of GDI+.
         // pdfdraw.SetRasterizerType(PDFRasterizer.Type.e_BuiltIn);
         // pdfdraw.SetDPI(200);
      }

#if NET_1_1

      [System.Runtime.InteropServices.DllImport("gdi32.dll")]
      private static extern int GetDeviceCaps(IntPtr hdc, int nIndex); 
      private const int PHYSICALOFFSETX = 112; 
      private const int PHYSICALOFFSETY = 113;

#endif

      private void OnPrintPDFPage(object sender, PrintPageEventArgs ev)
      {
         Graphics gr = ev.Graphics;
         gr.PageUnit = GraphicsUnit.Inch;
         bool use_hard_margins = false;
         Rectangle rectPage = ev.PageBounds;         //print without margins
         //Rectangle rectPage = ev.MarginBounds;     //print using margins
         double left, right, top, bottom;

         if (use_hard_margins) // You could adjust the rectangle to account for hard and soft margins, etc.
         {

#if NET_1_1

            // This code is used to obtain printer hard margins when running on .NET 1.1x or below. 
            IntPtr hdc = new IntPtr();
            hdc = ev.Graphics.GetHdc(); // Get handle to device context.
            double hardMarginX = GetDeviceCaps(hdc, PHYSICALOFFSETX);
            double hardMarginY  = GetDeviceCaps(hdc, PHYSICALOFFSETY);		
            ev.Graphics.ReleaseHdc(hdc); // Release handle to device context.

#else

            // If you are running on .NET Framework 2.x or above, you can directly access 'hard margin' property.
            double hardMarginX = ev.PageSettings.HardMarginX;
            double hardMarginY = ev.PageSettings.HardMarginY;

#endif

            left = (rectPage.Left - hardMarginX) / 100.0;
            right = (rectPage.Right - hardMarginX) / 100.0;
            top = (rectPage.Top - hardMarginY) / 100.0;
            bottom = (rectPage.Bottom - hardMarginY) / 100.0;
         }
         else 
         {

            left= rectPage.Left / 100.0;
            right = rectPage.Right / 100.0;
            top = rectPage.Top / 100.0;
            bottom= rectPage.Bottom / 100.0;
         }

         // The above page dimensions are in inches. We need to convert 
         // the page dimensions to PDF units (or points). One point is 
         // 1/72 of an inch.
         pdftron.PDF.Rect rect = new Rect(left*72, bottom*72, right*72, top*72);

         PDFDoc pdfdoc = GetPDFDoc();
         if (pdfdoc == null) 
         {
            MessageBox.Show("Error: Print document is not selected.");
            return;
         }
         pdfdoc.Lock();

         try 
         {
            if (print_page_itr.HasNext()) 
            {
               _pdfdraw.DrawInRect(print_page_itr.Current(), gr, rect);

               // Move to the next page, or finish printing
               print_page_itr.Next();
               ev.HasMorePages = print_page_itr.HasNext();
            }
            else ev.HasMorePages = false;
         } 
         catch (Exception ex)
         {
            MessageBox.Show("Printing Error: " + ex.ToString());
         }
         pdfdoc.Unlock(); 
      }

#endif

      private void InitializeComponent()
      {
         System.Resources.ResourceManager resources = new System.Resources.ResourceManager(typeof(PDFViewForm));

         // 
         // PDFViewForm
         // 
         this.BackColor = System.Drawing.SystemColors.Control;
         this.Cursor = System.Windows.Forms.Cursors.Hand;
         this.Icon = ((System.Drawing.Icon)(resources.GetObject("$this.Icon")));
         this.KeyPreview = true;
         this.Name = "PDFViewForm";
         this.Text = "PDFViewForm";
         this.WindowState = System.Windows.Forms.FormWindowState.Maximized;
      }
   }
}
```

{% endcode %}
{% endtab %}

{% tab title="VB" %}
{% code lineNumbers="true" %}

```vb
Imports System
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Drawing.Printing
Imports System.Collections
Imports System.ComponentModel
Imports System.Windows.Forms
Imports pdftron
Imports pdftron.PDF
Imports pdftron.Common
Imports System.Windows.Forms.VisualStyles.VisualStyleElement

Public Class PDFViewForm

   Inherits System.Windows.Forms.Form

   ' <summary>
   ' Required designer variable.
   ' </summary>
   Private components As System.ComponentModel.Container = Nothing

#If CUSTOM_NAV Then

   'The following variables are used for custom page navigation pane...
   Private _pdfdoc_tab As System.Windows.Forms.TabControl
   Private _bookmarks_tab As System.Windows.Forms.TabPage
   Private _pages_tab As System.Windows.Forms.TabPage
   Private _layers_tab As System.Windows.Forms.TabPage
   Private bookmark_tree As System.Windows.Forms.TreeView
   Private layer_tree As System.Windows.Forms.TreeView 
   Private splitter1 As System.Windows.Forms.Splitter
   Private _thumbview As ThumbView  = Nothing 'Custom thumbnail view.

#End If

   Private _pdfdoc As PDFDoc = Nothing ' Currently open PDF document.
   Private _pdfview As MyPDFView = Nothing ' Main PDF view.

   Public Sub New(ByVal main_form As MainForm)

      Me.MdiParent = main_form

      ' Create the main PDFViewCtrl control (we do it here manually for greater control)
      _pdfview = New MyPDFView(Me)
      _pdfview.Location = New System.Drawing.Point(0, 0) 'Added 'System.Drawing' to distinguish from PDF.Point to resolve compilaiton error
      _pdfview.Dock = System.Windows.Forms.DockStyle.Fill

      'Optional: Set the error and current page delegates...
      _pdfview.SetErrorReportHandler(AddressOf ErrorMsg, Nothing)
      _pdfview.SetCurrentPageHandler(AddressOf UpdateStatusBar, main_form)
      Controls.Add(_pdfview)

      ' Create other controls created using Windows Form Designer
      InitializeComponent()

   End Sub

   Public Function OpenPDF(ByVal filename As String) As Boolean
      Try
         Try
            ' Try to open as a PDF document
            _pdfdoc = New PDFDoc(filename)
         Catch ex As Exception
            ' Try to open as a PNG, JPEG, TIF, BMP, GIF, etc.
            _pdfdoc = OpenImage(filename)

            If _pdfdoc Is Nothing Then

               ' rethrow the original exception
               Throw ex
            End If
         End Try

         If Not _pdfdoc.InitSecurityHandler Then ' In case _pdfdoc is encrypted
            MessageBox.Show("Document authentication error", "PDFViewCtrl Error")
            Return False
         End If

#If CUSTOM_NAV Then

            ' Populates a custom bookmark tree control with bookmark nodes (if any). 
            Dim root As Bookmark = _pdfdoc.GetFirstBookmark()
            If root.IsValid Then
                bookmark_tree.BeginUpdate()
                FillBookmarkTree(root, bookmark_tree.Nodes)
                bookmark_tree.EndUpdate()
            Else
                ' Optional: Uncomment the following line to hide the bookmark 
                ' tab if the document does not contain bookmarks?:
                ' _pdfdoc_tab.Hide()
            End If

#End If

         ' Optional: Set page view and page presentation mode.
         ' _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_page)
         ' _pdfview.SetPageViewMode(PDFViewCtrl.PageViewMode.e_fit_page)

         If _pdfdoc.GetPageCount() > 2000 Then

            ' If the document has many pages use single page mode to seed up initial rendering.
            _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_page)

         End If

         _pdfview.SetDoc(_pdfdoc)

#If CUSTOM_NAV Then

            _thumbview.SetDoc(_pdfdoc, _pdfview)

#End If

         SetToolMode(MyPDFView._base_tool_mode, MyPDFView._tool_mode)
      Catch ex As PDFNetException

         MessageBox.Show(ex.Message)
         Return False

      Catch ex As Exception

         MessageBox.Show(ex.ToString)
         Return False

      End Try

      Me.Text = filename ' Set the title

      Return True

   End Function

   '  A utility function used to display other images types besides PDF 
   '  inside MyPDFView. This functionality can be used to display TIF, JPEG, 
   ' BMP, PNG, etc.
   Public Function OpenImage(ByVal filename As String) As PDFDoc

      Try
         Dim pdfDoc As PDFDoc = New PDFDoc ' create new document 
         Dim f As ElementBuilder = New ElementBuilder
         Dim writer As ElementWriter = New ElementWriter
         Dim page As Page = pdfDoc.PageCreate ' Add a blank page 
         writer.Begin(page)

         ' Add image to the document. 
         Dim img As pdftron.PDF.Image = pdftron.PDF.Image.Create(pdfDoc.GetSDFDoc(), filename)

         ' get image rectangle 
         Dim imgBox As Rect = New Rect(0, 0, img.GetImageWidth, img.GetImageHeight)
         Dim scaledBox As Rect = New Rect
         Dim scaleFactor As Double
         If imgBox.Height / imgBox.Width > 792 / 612 Then
            scaleFactor = imgBox.Height / 792
         Else
            scaleFactor = imgBox.Width / 612
         End If

         scaledBox.x2 = imgBox.x2 / scaleFactor
         scaledBox.y2 = imgBox.y2 / scaleFactor

         ' set crop and media box of this page to fit with the scaled image 
         page.SetCropBox(scaledBox)
         page.SetMediaBox(scaledBox)

         ' create the image element and add it to the page
         Dim width As Integer = CType(scaledBox.Width, Integer)
         Dim height As Integer = CType(scaledBox.Height, Integer)
         Dim offsetX As Integer = 0
         Dim offsetY As Integer = 0
         Dim element As Element = f.CreateImage(img, New Matrix2D(width, 0, 0, height, offsetX, offsetY))
         writer.WritePlacedElement(element)
         writer.End() ' Finish writing to the page 
         pdfDoc.PagePushBack(page)

         Return pdfDoc

      Catch ex As Exception

         ' MessageBox.Show(ex.ToString)
         Return Nothing
      End Try

   End Function

   Public Function GetPDFDoc() As PDFDoc
      If _pdfview Is Nothing Then
         Return Nothing
      Else
         Return _pdfview.GetDoc
      End If
   End Function
   Public Sub FitPage()
      _pdfview.SetPageViewMode(PDFViewCtrl.PageViewMode.e_fit_page)
   End Sub

   Public Sub FitWidth()
      _pdfview.SetPageViewMode(PDFViewCtrl.PageViewMode.e_fit_width)
   End Sub

   Public Sub ZoomIn()
      _pdfview.SetZoom(_pdfview.GetZoom * 2)
   End Sub

   Public Sub ZoomOut()
      _pdfview.SetZoom(_pdfview.GetZoom / 2)
   End Sub

   Public Sub FirstPage()
      _pdfview.GotoFirstPage()
   End Sub

   Public Sub PrevPage()
      _pdfview.GotoPreviousPage()
   End Sub

   Public Sub NextPage()
      _pdfview.GotoNextPage()
   End Sub

   Public Sub LastPage()
      _pdfview.GotoLastPage()
   End Sub

   Public Sub PageSingle()
      _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_page)
   End Sub
   Public Sub PageSingleContinuous()
      _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_single_continuous)
   End Sub

   Public Sub PageFacingContinuous()
      _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_facing_continuous)
   End Sub

   Public Sub PageFacing()
      _pdfview.SetPagePresentationMode(PDFViewCtrl.PagePresentationMode.e_facing)
   End Sub

   Public Sub RotateClockwise()
      _pdfview.RotateClockwise()
   End Sub

   Public Sub RotateCounterClockwise()
      _pdfview.RotateCounterClockwise()
   End Sub
   Public Sub SetAntiAliasing(ByVal anti_alias As Boolean)
      _pdfview.SetAntiAliasing(anti_alias)
      _pdfview.Update()
   End Sub

   Public Sub SetRasterizer(ByVal built_in As Boolean)
      If built_in Then
         _pdfview.SetRasterizerType(PDFRasterizer.Type.e_BuiltIn)
      Else
         _pdfview.SetRasterizerType(PDFRasterizer.Type.e_GDIPlus)
      End If

      _pdfview.Update()
   End Sub

   Public Sub SetSmoothImages(ByVal smooth_images As Boolean)
      _pdfview.SetImageSmoothing(smooth_images)
      _pdfview.Update()
   End Sub

   Public Sub Save(ByVal filename As String)
      If _pdfdoc Is Nothing Then
         Return
      End If

      _pdfdoc.Lock()

      Try
         If Not (_pdfview Is Nothing) Then
            ' Check if there are any annotations that need to 
            ' be merged with the document.
            If Not (_pdfview._freehand_markup Is Nothing) Then
               For Each itr As DictionaryEntry In _pdfview._freehand_markup
                  Dim annot_page_num As Integer = CType(itr.Key, Integer)
                  Dim pg As Page = _pdfdoc.GetPage(annot_page_num)
                  If Not pg Is Nothing Then
                     Dim annot As FreeHandAnnot = CType(itr.Value, FreeHandAnnot)
                     annot.DrawAnnots(pg, Pens.Red)
                  End If
               Next

               _pdfview._freehand_markup = Nothing
               _pdfview.Invalidate()
               _pdfview.Update()
            End If
         End If

         _pdfdoc.Save(filename, pdftron.SDF.SDFDoc.SaveOptions.e_remove_unused)

      Catch ex As Exception
         MessageBox.Show(ex.ToString(), "Error during the Save")
      End Try

      _pdfdoc.Unlock()

   End Sub

   Public Sub SaveAs()
      If Not (_pdfdoc Is Nothing) AndAlso Not (_pdfview Is Nothing) Then

         'opens a save dialog
         Dim dlg As SaveFileDialog = New SaveFileDialog
         dlg.Filter = "PDF Files (*.pdf)|*.pdf|All Files (*.*)|*.*"
         dlg.DefaultExt = ".pdf"
         dlg.FileName = Text
         Dim res As DialogResult = dlg.ShowDialog
         If res = DialogResult.OK Then
            'saves the file
            Me.Save(dlg.FileName)
         End If
      End If
   End Sub

   Protected Overloads Overrides Sub OnClosing(ByVal e As CancelEventArgs)

      'called when user closes a document
      If Not (_pdfdoc Is Nothing) AndAlso Not (_pdfview Is Nothing) AndAlso (_pdfdoc.IsModified OrElse Not (_pdfview._freehand_markup Is Nothing)) Then

         'if the document exists and is modified then ask the user
         'whether or not to save it
         Dim save As DialogResult = MessageBox.Show("Would you like to save the changes to the document?", "PDFViewCtrl", MessageBoxButtons.YesNoCancel)

         If save = DialogResult.Yes Then
            'opens a save dialog
            Dim dlg As SaveFileDialog = New SaveFileDialog
            dlg.Filter = "PDF Files (*.pdf)|*.pdf|All Files (*.*)|*.*"
            dlg.DefaultExt = ".pdf"
            dlg.FileName = Text
            Dim res As DialogResult = dlg.ShowDialog
            If res = DialogResult.OK Then
               'saves the file
               Me.Save(dlg.FileName)
            Else
               If res = DialogResult.Cancel Then
                  e.Cancel = True
               End If
            End If
         Else
            If save = DialogResult.Cancel Then
               e.Cancel = True
            End If
         End If

         MyBase.OnClosing(e)
      End If
   End Sub

   ' <summary>
   ' Clean up any resources being used.
   ' </summary>
   Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
      If disposing Then

#If CUSTOM_NAV Then

            _thumbview.Dispose()  ' Close the thumbnail view.

#End If

         _pdfview.Dispose()    ' Close the open PDF document in the view.
         _pdfdoc.Dispose()     ' Close the PDF document.
         If Not (components Is Nothing) Then
            components.Dispose()
         End If
      End If

      MyBase.Dispose(disposing)
   End Sub

   ' <summary>
   '  This callback method (delegate) was registered using _pdfview.SetErrorReportProc 
   '  in PDFViewCS constructor. The callback can be used to report any errors that may 
   '  occur during page rendering.
   ' </summary>

   Public Shared Sub ErrorMsg(ByVal message As String, ByVal obj As Object)
      MessageBox.Show(message, "PDFViewCtrl Error")
   End Sub

#If CUSTOM_NAV Then 'Custom bookmark and PDF layer navigation sample

    ' Handle the the bookmark select event (i.e. when the user selects a node in the bookmark tree).
    Private Sub BookmarkTreeAfterSelect(ByVal sender As System.Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles bookmark_tree.AfterSelect
      _pdfdoc.Lock()
      Dim item As Bookmark = CType(e.Node.Tag, Bookmark)
      Dim action As Action = item.GetAction
      If action.IsValid Then    ' Handle goto actions.
         ' Other types of actions can be handled in similar way.
         If action.GetType = action.Type.e_GoTo Then
            Dim dest As Destination = action.GetDest
            If dest.IsValid() Then
            Dim page As Page = dest.GetPage
               If Not page Is Nothing Then
                  _pdfview.SetCurrentPage(page.GetIndex)
               End If
            End If
         End If
      End If

      _pdfdoc.Unlock()
    End Sub

   ' Populate the tree control with bookmark items.
   Shared Sub FillBookmarkTree(ByVal item As Bookmark, ByVal nodes As TreeNodeCollection)
       Dim i As Integer = 0
       While item.IsValid
           Dim new_node As TreeNode = New TreeNode(item.GetTitle)
           nodes.Add(new_node)
           new_node.Tag = item
           If item.IsOpen Then
               new_node.Expand()
           End If
           If item.HasChildren Then    ' Recursively add children sub-trees
               FillBookmarkTree(item.GetFirstChild, new_node.Nodes)
           End If
           item = item.GetNext
           i = i + 1
       End While
   End Sub

#End If

   ' <summary>
   ' This callback method (delegate) was registered using _pdfview.SetCurrentPageProc 
   '  in PDFViewCS constructor. The callback can be used to update the current page number
   '  within GUI applications etc. In this case we update the status bar in the main form.
   ' </summary>
   Public Shared Sub UpdateStatusBar(ByVal current_page As Integer, ByVal num_pages As Integer, ByVal data As Object)
      If Not (data Is Nothing) Then
         Dim main_form As MainForm = CType(data, MainForm)
         main_form._current_page = current_page
         main_form._num_pages = num_pages
         main_form.UpdateStatusBar(current_page, num_pages)
      End If
   End Sub

   Public Sub SetToolMode(ByVal tool_mode As MyPDFView.CustomToolMode, ByVal custom_tool_mode As MyPDFView.CustomToolMode)
      ' Set the custom tool mode.
      MyPDFView._base_tool_mode = tool_mode
      MyPDFView._tool_mode = custom_tool_mode
      'Chaged by Kay April1------------------------
      'Set built-in tool mode (pan, text select, or custom)
      'Dim tm As PDFViewCtrl.ToolMode
      'If (tool_mode = MyPDFView.CustomToolMode.e_pan) Then
      '    tm = PDFViewCtrl.ToolMode.e_pan
      'ElseIf (tool_mode = MyPDFView.CustomToolMode.e_text_struct_select) Then
      '    tm = PDFViewCtrl.ToolMode.e_text_struct_select
      'ElseIf (tool_mode = MyPDFView.CustomToolMode.e_text_rect_select) Then
      '    tm = PDFViewCtrl.ToolMode.e_text_rect_select
      'Else
      '    tm = PDFViewCtrl.ToolMode.e_custom
      'End If
      'Chaged by Kay April1------------------------
      _pdfview.SetToolMode(tool_mode)
   End Sub

   Protected Overloads Overrides Sub OnActivated(ByVal e As EventArgs)
      If Not (_pdfview Is Nothing) Then
         Dim main_form As MainForm = CType(Me.MdiParent, MainForm)
         main_form._current_page = _pdfview.GetCurrentPage
         main_form._num_pages = _pdfview.GetDoc.GetPageCount
         main_form.UpdateStatusBar(_pdfview.GetCurrentPage(), _pdfview.GetDoc().GetPageCount())
      End If
   End Sub

   Private Sub InitializeComponent()
      Dim resources As System.Resources.ResourceManager = New System.Resources.ResourceManager(GetType(PDFViewForm))
      'PDFViewForm
      '
      Me.BackColor = System.Drawing.SystemColors.Control
      Me.Cursor = System.Windows.Forms.Cursors.Hand
      Me.Icon = CType(resources.GetObject("$this.Icon"), System.Drawing.Icon)
      Me.KeyPreview = True
      Me.Name = "PDFViewForm"
      Me.Text = "PDFViewForm"
      Me.WindowState = System.Windows.Forms.FormWindowState.Maximized
   End Sub

   Public Sub Export()
      Dim temp As ExportDialog = New ExportDialog(Me._pdfdoc)
   End Sub

   Public Sub CopySelectedText()
      _pdfview.OnTextCopy(Nothing, Nothing)
   End Sub

   Public Sub SelectAll()
      _pdfview.SelectAll()
   End Sub

   Public Sub DeselectAll()
      _pdfview.ClearSelection()
   End Sub

   Public Sub FindText()
      _pdfview.Find() 'Use the build in Find text dialog.
   End Sub

   ' Private members used for print support -------------------------
   ' In this sample, PDFDraw object is used to implement print support.
   Private pdfdraw As PDFDraw = Nothing
   Private print_page_itr As PageIterator

   Public Sub Print()
      Try

#If CUSTOM_PRINT Then

            Dim print_dlg As PrintDialog = New PrintDialog
            print_dlg.AllowSomePages = True
            print_dlg.Document = print_doc
            If (print_dlg.ShowDialog() = DialogResult.OK) Then
               pdfdraw = new PDFDraw
               pdfdraw.SetPrintMode(True)
               _print_doc.Print()
               pdfdraw.Dispose()
               pdfdraw = Nothing
            End If

#Else

         _pdfview.Print()

#End If

      Catch ex As Exception
         MessageBox.Show(ex.ToString())
      End Try
   End Sub

   '  Me.print_doc.BeginPrint += New System.Drawing.Printing.PrintEventHandler(this.OnBeginPDFPrint)
   '  Me.print_doc.PrintPage += New System.Drawing.Printing.PrintPageEventHandler(this.OnPrintPDFPage)

#If CUSTOM_PRINT Then

    Private Sub OnBeginPDFPrint(ByVal sender As System.Object, ByVal ev As System.Drawing.Printing.PrintEventArgs) Handles print_doc.BeginPrint
        Dim doc As PDFDoc = GetPDFDoc()
        If doc Is Nothing Then
            MessageBox.Show("Error: Print document is not selected.")
            Return
        End If
        print_page_itr = doc.GetPageIterator()

        ' PDFNet includes two different rasterizer implementations. 
        '
        ' The two implementations offer a trade-off between print
        ' speed and accuracy/quality, as well as a trade-off between 
        ' vector and raster output.
        '
        ' e_GDIPlus rasterizer can be used to render the page 
        ' using Windows GDI+, whereas e_BuiltIn rasterizer can
        ' be used to render bitmaps using platform-independent 
        ' graphics engine (in this case images are always converted 
        ' to bitmap prior to printing).
        pdfdraw.SetRasterizerType(PDFRasterizer.Type.e_GDIPlus)

        ' You can uncomment the following lines in order to use 
        ' built-in, platform-independent rasterizer instead of GDI+.
        ' pdfdraw.SetRasterizerType(PDFRasterizer.Type.e_BuiltIn)
        ' pdfdraw.SetDPI(200)
    End Sub

#if NET_1_1

    <System.Runtime.InteropServices.DllImport("gdi32.dll")> Private Shared Function GetDeviceCaps(ByVal hdc As IntPtr, ByVal nIndex As Integer) As Integer
    End Function

    Private Const PHYSICALOFFSETX As Integer = 112
    Private Const PHYSICALOFFSETY As Integer = 113

    #endif

   Private Sub OnPrintPDFPage(ByVal sender As Object, ByVal ev As PrintPageEventArgs)'Handles print_doc.PrintPage
      Dim gr As Graphics = ev.Graphics
      gr.PageUnit = GraphicsUnit.Inch
      Dim use_hard_margins As Boolean =False
      Dim rectPage As Rectangle=ev.PageBounds 'print without margins
      Dim left As Double
      Dim right As Double
      Dim top As Double
      Dim bottom As Double
      If use_hard_margins Is True Then

#if NET_1_1

      ' This code is used to obtain printer hard margins when running on .NET 1.1x or below. 
      Dim hdc As IntPtr = new IntPtr
      hdc = ev.Graphics.GetHdc(); 'Get handle to device context.
      Dim hardMarginX As Double = GetDeviceCaps(hdc, PHYSICALOFFSETX)
      Dim hardMarginY As Double = GetDeviceCaps(hdc, PHYSICALOFFSETY)
      ev.Graphics.ReleaseHdc(hdc) 'Release handle to device context.

#else 

            ' If you are running on .NET Framework 2.x or above, you can directly access 'hard margin' property.
            Dim hardMarginX As Double = ev.PageSettings.HardMarginX
            Dim hardMarginY As Double = ev.PageSettings.HardMarginY

#endif

            left = (rectPage.Left - hardMarginX) / 100.0
            right = (rectPage.Right - hardMarginX) / 100.0
            top = (rectPage.Top - hardMarginY) / 100.0
            bottom = (rectPage.Bottom - hardMarginY) / 100.0
         Else 
            left= rectPage.Left / 100.0;
            right = rectPage.Right / 100.0;
            top = rectPage.Top / 100.0;
            bottom= rectPage.Bottom / 100.0;
         End If

         'The above page dimensions are in inches. We need to convert 
         'the page dimensions to PDF units (or points). One point is 
         '1/72 of an inch.
         Dim rect As pdftron.PDF.Rect = new Rect(left*72, bottom*72, right*72, top*72)
         Dime pdfdoc As PDFDoc = GetPDFDoc()
         pdfdoc.Lock()

         Try
            If print_page_itr.HasNext() Then 
               _pdfdraw.DrawInRect(print_page_itr.Current(), gr, rect)

               'Move to the next page, or finish printing
               print_page_itr.Next()
               ev.HasMorePages = print_page_itr.HasNext()
            else ev.HasMorePages = False
         Catch ex As Exception
            MessageBox.Show("Printing Error: " + ex.ToString)
         End Try
         pdfdoc.Unlock() 
   End Sub

#End If

End Class
```

{% endcode %}
{% endtab %}
{% endtabs %}


---

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