This section provides information about the following:

PDF Samples and Tutorials

Our suite of PDF samples will help you get started using ImageGear's PDF capabilities.

This section also provides step-by-step PDF tutorials, which show you how to create a new ImageGear project using the PDF component:

ImageGear.Formats.PDF Namespace

The ImageGear.Formats.PDF namespace allows you to load, save, and process native PDF and PostScript documents. It also allows rasterization of PDF and PostScript documents, by converting them to bitmaps, and provides you with the ability to extract text from loaded PDF and PostScript documents.

The ImageGear.Formats.PDF namespace provides full multi-page read and write support for the entire document as well as a specified set of pages. You can detect, read, write, append, insert, replace, swap, and delete a specified page in the PDF document as well as to edit its content.

To enable the ImageGear.Formats.PDF Namespace in your project, specify the following directive:

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using ImageGear.Formats.PDF;

PDF Dependencies

You can use our NuGet packages to ensure you have met all required dependencies.

NuGet Packages

NuGet packages make it easy to add, remove, and update libraries and tools in Visual Studio projects that use the .NET Framework. See NuGet Packages for more information.

PDF Object Lifetime

Many PDF objects are disposable. This means that the Dispose() method must be called, either explicitly or via a “using” statement, when the newly created PDF object is no longer needed.

Disposable PDF objects:

ImGearPDFDocument - derived from Disposable ImGearDocument
ImGearPDFPage
ImGearPDFObject - base class for many PDF objects, such as ImGearPDEContent, ImGearPDFLayer, ImGearPDFWordFinder, etc.

Example - "using" statement:

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using (Stream stream = new FileStream(fileName, FileMode.Open, FileAccess.Read)) { // Load new document using (ImGearPDFDocument document = ImGearFileFormats.LoadDocument(stream, FIRST_PAGE, ALL_PAGES) as ImGearPDFDocument) { // Clone page using (ImGearPDFPage page = document.Pages[0].Clone() as ImGearPDFPage) { // Get page content using (ImGearPDEContent content = page.GetContent()) { // Do something. page.ReleaseContent(); } } } }

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using (Stream stream = new FileStream(fileName, FileMode.Open, FileAccess.Read))
{
    // Load new document
    using (ImGearPDFDocument document = ImGearFileFormats.LoadDocument(stream, FIRST_PAGE, ALL_PAGES) as ImGearPDFDocument)
    {
        // Clone page
        using (ImGearPDFPage page = document.Pages[0].Clone() as ImGearPDFPage)
        {
            // Get page content
            using (ImGearPDEContent content = page.GetContent())
            {
                // Do something.
                page.ReleaseContent();
            }
        }
    }
}

Example - Explicit call to Dispose():

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using (Stream stream = new FileStream(fileName, FileMode.Open, FileAccess.Read)) { // Load new document ImGearPDFDocument document = ImGearFileFormats.LoadDocument(stream, FIRST_PAGE, ALL_PAGES) as ImGearPDFDocument; // Clone page ImGearPDFPage page = document.Pages[0].Clone() as ImGearPDFPage; // Get page content ImGearPDEContent content = page.GetContent(); // Do something page.ReleaseContent(); content.Dispose(); page.Dispose(); document.Dispose(); }

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using (Stream stream = new FileStream(fileName, FileMode.Open, FileAccess.Read))
{
    // Load new document
    ImGearPDFDocument document = ImGearFileFormats.LoadDocument(stream, FIRST_PAGE, ALL_PAGES) as ImGearPDFDocument;
    // Clone page
    ImGearPDFPage page = document.Pages[0].Clone() as ImGearPDFPage;
    // Get page content
    ImGearPDEContent content = page.GetContent();
    // Do something
    page.ReleaseContent();
    content.Dispose();
    page.Dispose();
    document.Dispose();
}

Note that the Dispose() method should not be called for the PDF page when the page is obtained from a PDF page array by index because there is no newly created instance of ImGearPDFPage in this case.

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// Dispose() is not needed for page ImGearPDFPage page = document.Pages[0] as ImGearPDFPage;

All PDF objects, such as ImGearPDEColorspace, ImGearPDFPage, and ImGearPDEContent, are based on underlying low-level PDF objects, which are not controlled by .NET resource manager and garbage collector. Due to complex dependencies between these objects, it is not possible to wrap these objects with a fully-automated .NET lifecycle management. For example, disposing an ImGearPDFPage object whose content was obtained with the GetContent method and was not released with ReleaseContent can lead to an internal PDF exception.

Failure to dispose of PDF Documents and Pages can cause significant memory issues in the running application and lingering issues, in the form of abandoned temp files, after the application has terminated.

Also, an ImGearPDEContent object obtained from ImGearPDFPage should be released using the ImGearPDFPage.ReleaseContent() method in all cases.

An ImGearPDEContent object obtained from a Container, Group, or Form does not need to be released, so ImGearPDEContainer, ImGearPDEForm, and ImGearPDEGroup do not have such a method.

Here is sample code to illustrate this:

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public void IterateElements(ImGearDocument imageDocument) { ImGearPDFDocument pdfDocument = (ImGearPDFDocument)imageDocument; for (int index = 0; index < pdfDocument.Pages.Count; index++) { try { ImGearPage page = pdfDocument.Pages[index]; // content should be disposed ImGearPDEContent content = ((ImGearPDFPage)page).GetContent(); for (int elementIndex = 0; elementIndex < content.ElementCount; elementIndex++) { ImGearPDEElement element = content.GetElement(elementIndex); if (!TryLoadElement(element)) { throw new Exception(); } element.Dispose(); } // ReleaseContent should be called for a page ((ImGearPDFPage)page).ReleaseContent(); // dispose content content.Dispose(); } catch (Exception ex) { MessageBox.Show("Error”); } } // ImGearPDFDocument object should be disposed too. We’ve left it to caller. }

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public void IterateElements(ImGearDocument imageDocument)
        {
            ImGearPDFDocument pdfDocument = (ImGearPDFDocument)imageDocument;
 
            for (int index = 0; index < pdfDocument.Pages.Count; index++)
            {
                try
                {
                    ImGearPage page = pdfDocument.Pages[index];
                 // content should be disposed
                    ImGearPDEContent content = ((ImGearPDFPage)page).GetContent();
                    for (int elementIndex = 0; elementIndex < content.ElementCount; elementIndex++)
                    {
                        ImGearPDEElement element = content.GetElement(elementIndex);
                        if (!TryLoadElement(element))
                        {
                            throw new Exception();
                       }
                        element.Dispose();
                    }
                   
                    // ReleaseContent should be called for a page
                    ((ImGearPDFPage)page).ReleaseContent();
                    // dispose content
                    content.Dispose();
                }
                catch (Exception ex)
                {
                    MessageBox.Show("Error”);
                }
            }
            // ImGearPDFDocument object should be disposed too. We’ve left it to caller.
        }

Working with PS Files

The ImageGear.Formats.PDF namespace loads PostScript files by converting them to PDF first and applying a set of default conversion settings. To adjust the results of that conversion, ImageGear PDF namespace implements JobOptionsFile PostScript filter control parameter that can be pointed to one of the .joboptions files distributed with the product. A .joboptions file contains settings that control the conversion from PostScript or EPS to PDF performed on-the-fly for rendering PostScript and EPS in ImageGear. If you encounter any problems with PostScript or EPS rendering or conversion to PDF, such as color or layout differences, you can use the provided "Bin\Resource\PS\Settings\Standard.joboptions" by setting the value of JobOptionsFile PostScript filter control parameter to the full path of the location of that file.