The most common and widely used word-processing file formats are DOC, DOCX, and ODT. The famous Microsoft Word and OpenOffice Writer support these formats and we normally use these formats for drafting the documents. Therefore, as a developer, we widely need to edit Word documents in our applications programmatically. In this article, we will discuss how to edit Word documents in C# using the .NET API for document editing.

The following are the topics discussed briefly in this article:

.NET API for Word Documents Editing and Automation

In this article, I will be using GroupDocs.Editor for .NET in C# examples, which is the document editing API and allows developers to load, edit, and save various document formats using WYSIWYG HTML editors. In addition to the word-processing document formats, the API supports editing spreadsheets, presentations, HTML, XML, TXT, DSV, TSV, and CSV formats.

Download the DLLs or MSI installer from the downloads section or install the API in your .NET application via NuGet.

PM> Install-Package GroupDocs.Editor

Edit Word Documents in C#

Just after setting up the API, you can quickly move towards editing the Word document. The following steps will let you edit the word-processing document.

  • Load the Word document.
  • Edit accordingly with options.
  • Save the edited document.

Load the Word document

Firstly, load the document by providing the document path and the password, if the document is protected.

using (FileStream fs = File.OpenRead(inputFilePath))
    Options.WordProcessingLoadOptions loadOptions = new WordProcessingLoadOptions();
    loadOptions.Password = "password-if-any";

Edit the Word document

After loading, you can edit the loaded document as per your requirement. Here I am replacing all the occurrences of word “document” with the “edited document” in a Word document using the below C# code.

    using (Editor editor = new Editor(delegate { return fs; }, delegate { return loadOptions; }))
        Options.WordProcessingEditOptions editOptions = new WordProcessingEditOptions();
        editOptions.FontExtraction = FontExtractionOptions.ExtractEmbeddedWithoutSystem;
        editOptions.EnableLanguageInformation = true;
        editOptions.EnablePagination = true;
        using (EditableDocument beforeEdit = editor.Edit(editOptions))
            string originalContent = beforeEdit.GetContent();
            List<IHtmlResource> allResources = beforeEdit.AllResources;
            string editedContent = originalContent.Replace("document", "edited document");

Save the Edited Word document with Options

Lastly, while saving the edited document content, you can further set various options. These options include; pagination, set password, locale, protection, or memory optimization settings. I set the above options in the below-mentioned code and save the edited document as a password-protected and read-only DOCX file.

using (EditableDocument afterEdit = EditableDocument.FromMarkup(editedContent, allResources))
    Options.WordProcessingSaveOptions saveOptions = new WordProcessingSaveOptions(WordProcessingFormats.Docx);
    saveOptions.EnablePagination = true;
    saveOptions.Locale = System.Globalization.CultureInfo.GetCultureInfo("en-US");
    saveOptions.OptimizeMemoryUsage = true;
    saveOptions.Password = "password";
    saveOptions.Protection = new WordProcessingProtection(WordProcessingProtectionType.ReadOnly, "write\_password");
    using (FileStream outputStream = File.Create("filepath/editedDocument.docx"))
        editor.Save(afterEdit, outputStream, saveOptions);

Complete Code

For your convenience, I am showing the complete C# example that is explained above and it edits the Word document and then saves it in DOCX format.

The following is the output document in which all the occurrences are replaced using the above code.

edited docx document using editor API

Output document - All the occurrences are replaced


To conclude, we discussed editing Word documents in C# using document editing API for .NET applications. You can use the API with WYSIWYG editors for the visual editing of your documents. After that, you can move ahead to build your own document editor. Similarly, you can also integrate the editing feature within your .NET application.

For more details, options, and examples, you can visit the documentation and the GitHub repository. For further queries, contact the support on the forum.

See Also