Tutorial: Document Writers Tutorial

Take the following steps to start a project and to add some code that creates an EMF file, adds some shapes and text, then uses LEADTOOLS Document Writers to convert the EMF file to PDF:

Start Visual Studio .NET.
Choose File->New->Project from the menu.
In the New Project dialog box, choose either "Visual C# Projects" or "Visual Basic Projects" in the Projects Type List, and choose "Windows Application" in the Templates List.
Type the project name as "DocumentWritersTutorial" in the Project Name field, and then click OK. If desired, type a new location for your project or select a directory using the Browse button, and then click OK.
In the Solution Explorer window, right-click on the References folder, and select "Add Reference..." from the context menu. In the "Add Reference" dialog box, select the ".NET" tab, browse to the "<LEADTOOLS_INSTALLDIR> \Bin\DotNet\Win32" folder, and select the following DLLs:
- Leadtools.dll
- Leadtools.Codecs.dll
- Leadtools.Codecs.Raw.dll
- Leadtools.Codecs.Tif.dll
- Leadtools.Codecs.Bmp.dll
- Leadtools.Codecs.Cmp.dll
- Leadtools.Forms.dll
- Leadtools.Forms.DocumentWriters.dll
Click the Select button and then press the OK button to add the above DLLs to the application.

Make sure Form1 is in design view. Go to the toolbox (View->Toolbox from the menu) and add the following controls to the form:

Type	Name	Text
Button	convertEmfToPdfButton	Convert EMF to PDF
CheckBox	imageOverTextCheckBox	Image over text
CheckBox	pdfACheckBox	pdf/a

Switch to Form1 code view (right-click Form1 in the solution explorer then select View Code) and add the following lines at the beginning of the file:

[Visual Basic]


            Imports System.IO
            Imports System.Diagnostics
            Imports System.Runtime.InteropServices
            Imports Leadtools
            Imports Leadtools.Codecs
            Imports Leadtools.Forms.DocumentWriters

[C#]


            using System.IO;
            using System.Diagnostics;
            using System.Runtime.InteropServices;
            using Leadtools;
            using Leadtools.Codecs;
            using Leadtools.Forms.DocumentWriters;

Add the following code snippet to Form1:

[Visual Basic]


            ' Windows API functions used in this demo
            <DllImport("gdi32.dll")> _
            Private Shared Function GetEnhMetaFile(ByVal lpszMetaFile As String) As IntPtr
            End Function
            <DllImport("gdi32.dll")> _
            Private Shared Function DeleteEnhMetaFile(ByVal hemf As IntPtr) As Boolean
            End Function
            Private codecs As RasterCodecs ' RasterCodecs object to use when loading TIF files

[C#]


            // Windows API functions used in this demo
            [DllImport("gdi32.dll")]
            private static extern IntPtr GetEnhMetaFile(string lpszMetaFile);
            [DllImport("gdi32.dll")]
            private static extern bool DeleteEnhMetaFile(IntPtr hemf);
            private RasterCodecs codecs; // RasterCodecs object to use when loading TIF files

Add the following code to the Form1 constructor (in Visual Basic, you can copy/paste the whole Sub New code from here):

[Visual Basic]


            Public Sub New()
               ' This call is required by the Windows Form Designer.
               InitializeComponent()
               ' Add any initialization after the InitializeComponent() call.
               ' Replace with your own key
               
                 Dim MY_LICENSE_FILE As String = "d:\temp\TestLic.lic"
                  
                 ' Unlock the Document Writers support
                 Dim MY_DOCWRTDEVELOPER_KEY As String = "xyz123abc"
                 RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DOCWRTDEVELOPER_KEY)
                 
                 ' Unlock the Document Writers PDF support     
                 Dim MY_DOCPDFDEVELOPER_KEY As String = "abc123xyz"
                 RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DOCPDFDEVELOPER_KEY)
                 
                 ' Unlock the Document support     
                 Dim MY_DOCDEVELOPER_KEY As String = "123xyzabc"
                 RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DOCDEVELOPER_KEY)
                 
               ' Initialize RasterCodecs
               codecs = new RasterCodecs()
            End Sub

[C#]


            public Form1()
            {
               InitializeComponent();
               // Please replace with your own key
               
               string MY_LICENSE_FILE = "d:\\temp\\TestLic.lic";
               
               // Unlock Document Writers support
               string MY_DOCWRTDEVELOPER_KEY = "xyz123abc";
               RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DOCWRTDEVELOPER_KEY);
               
               // Unlock Document Writers PDF support
               string MY_DOCPDFDEVELOPER_KEY = "abc123xyz";
               RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DOCPDFDEVELOPER_KEY);
               
               // Unlock Document support
               string MY_DOCDEVELOPER_KEY = "123xyzabc";
               RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DOCDEVELOPER_KEY);
               // Initialize RasterCodecs
               codecs = new RasterCodecs();
            }

Add the following code as the OnFormClosed method for Form1 to clean up the resources used in the demo:

[Visual Basic]


            Protected Overrides Sub OnFormClosed(ByVal e As FormClosedEventArgs)
               ' Clean up
               codecs.Dispose()
            End Sub

[C#]


            protected override void OnFormClosed(FormClosedEventArgs e)
            {
               // Clean up
               codecs.Dispose();
            }

Add the following code for the convertEmfToPdfButton (Convert EMF to PDF) control's Click handler:

[Visual Basic]


            Private Sub convertEmfToPdfButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles convertEmfToPdfButton.Click
               ' Get the output file name
               Dim pdfFileName As String
               Using dlg As New SaveFileDialog()
                  ' Get the PDF friendly name and extension to use in the common dialog
                  Dim friendlyName As String = DocumentWriter.GetFormatFriendlyName(DocumentFormat.Pdf)
                  Dim extension As String = DocumentWriter.GetFormatFileExtension(DocumentFormat.Pdf)
                  dlg.Filter = String.Format("{0}(*.{1})|*.{1}|All Files|*.*", friendlyName, extension)
                  If (dlg.ShowDialog(Me) = DialogResult.OK) Then
                     pdfFileName = dlg.FileName
                  Else
                     Return
                  End If
               End Using
               ' Create an instance of the LEADTOOLS DocumentWriter
               Dim docWriter As New DocumentWriter()
               ' Set the PDF options
               Dim pdfOptions As PdfDocumentOptions = DirectCast(docWriter.GetOptions(DocumentFormat.Pdf), PdfDocumentOptions)
               Dim imageOverText As Boolean = imageOverTextCheckBox.Checked
               If (imageOverText) Then
                  pdfOptions.ImageOverText = True
               Else
                  pdfOptions.ImageOverText = False
               End If
               If (pdfACheckBox.Checked) Then
                  pdfOptions.DocumentType = PdfDocumentType.PdfA
               Else
                  pdfOptions.DocumentType = PdfDocumentType.Pdf
               End If
               docWriter.SetOptions(DocumentFormat.Pdf, pdfOptions)
               ' Begin a new PDF document
               docWriter.BeginDocument(pdfFileName, DocumentFormat.Pdf)
               ' Add the pages
               ' LEADTOOLS ships with Ocr1.emf to Ocr4.emf in the images folder
               Dim imagesFolder As String = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), "LEADTOOLS Images")
               For page As Integer = 1 To 4
                  ' Load the EMF
                  Dim emfFileName As String = Path.Combine(imagesFolder, String.Format("Ocr{0}.emf", page))
                  Dim tifFileName As String = Path.Combine(imagesFolder, String.Format("Ocr{0}.tif", page))
                  ' Add the page
                  Dim docPage As DocumentPage = DocumentPage.Empty
                  docPage.EmfHandle = GetEnhMetaFile(emfFileName)
                  If (imageOverText) Then
                     docPage.Image = codecs.Load(tifFileName)
                  Else
                     docPage.Image = Nothing
                  End If
                  docWriter.AddPage(docPage)
                  ' Clean up
                  If docPage.EmfHandle <> IntPtr.Zero Then
                     DeleteEnhMetaFile(docPage.EmfHandle)
                  End If
                  If Not IsNothing(docPage.Image) Then
                     docPage.Image.Dispose()
                  End If
               Next
               ' Finish the document
               docWriter.EndDocument()
               ' We successfuly created the PDF, ask the user if they want to view it
               Dim question As String = String.Format("PDF document was successfully created at {0}\n\nDo you want to view it now?", pdfFileName)
               If MessageBox.Show(Me, question, "DocumentWriter", MessageBoxButtons.YesNo, MessageBoxIcon.Question) = DialogResult.Yes Then
                  Process.Start(pdfFileName)
               End If
            End Sub

[C#]


            private void convertEmfToPdfButton_Click(object sender, EventArgs e)
            {
               // Get the output file name
               string pdfFileName;
               using(SaveFileDialog dlg = new SaveFileDialog())
               {
                  // Get the PDF friendly name and extension to use in the common dialog
                  string friendlyName = DocumentWriter.GetFormatFriendlyName(DocumentFormat.Pdf);
                  string extension = DocumentWriter.GetFormatFileExtension(DocumentFormat.Pdf);
                  dlg.Filter = string.Format("{0}(*.{1})|*.{1}|All Files|*.*", friendlyName, extension);
                  if(dlg.ShowDialog(this) == DialogResult.OK)
                     pdfFileName = dlg.FileName;
                  else
                     return;
               }
               // Create an instance of the LEADTOOLS DocumentWriter
               DocumentWriter docWriter = new DocumentWriter();
               // Set the PDF options
               PdfDocumentOptions pdfOptions = docWriter.GetOptions(DocumentFormat.Pdf) as PdfDocumentOptions;
               bool imageOverText = imageOverTextCheckBox.Checked;
               if(imageOverText)
                  pdfOptions.ImageOverText = true;
               else
                  pdfOptions.ImageOverText = false;
               if(pdfACheckBox.Checked)
                  pdfOptions.DocumentType = PdfDocumentType.PdfA;
               else
                  pdfOptions.DocumentType = PdfDocumentType.Pdf;
               docWriter.SetOptions(DocumentFormat.Pdf, pdfOptions);
               // Begin a new PDF document
               docWriter.BeginDocument(pdfFileName, DocumentFormat.Pdf);
               // Add the pages
               // LEADTOOLS ships with Ocr1.emf to Ocr4.emf in the images folder
               string imagesFolder = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"LEADTOOLS Images");
               for(int page = 1; page <= 4; page++)
               {
                  // Load the EMF
                  string emfFileName = Path.Combine(imagesFolder, string.Format("Ocr{0}.emf", page));
                  string tifFileName = Path.Combine(imagesFolder, string.Format("Ocr{0}.tif", page));
                  // Add the page
                  DocumentPage docPage = DocumentPage.Empty;
                  docPage.EmfHandle = GetEnhMetaFile(emfFileName);
                  if(imageOverText)
                     docPage.Image = codecs.Load(tifFileName);
                  else
                     docPage.Image = null;
                  docWriter.AddPage(docPage);
                  // Clean up
                  if(docPage.EmfHandle != IntPtr.Zero)
                     DeleteEnhMetaFile(docPage.EmfHandle);
                  if(docPage.Image != null)
                     docPage.Image.Dispose();
               }
               // Finish the document
               docWriter.EndDocument();
               // We successfuly created the PDF, ask the user if they want to view it
               string question = string.Format("PDF document was successfully created at {0}\n\nDo you want to view it now?", pdfFileName);
               if(MessageBox.Show(this, question, "DocumentWriter", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes)
               {
                  Process.Start(pdfFileName);
               }
            }

Build and Run the program to test it.
Click the "Convert EMF To PDF" button. Try with different options for the PDF file and check the results.
For information on using the LEADTOOLS Document Writers, see Programming with the LEADTOOLS Document Writers.

NOTE: If you encounter an "Invalid File Format" or "Feature Not Supported" exception, please refer to the topic Invalid File Format/Feature Not Supported.