How to Insert Merge Field at Bookmark in Word Document in .NET Core?

Syncfusion® Essential® DocIO is a .NET Word library used to create, read, edit, and convert Word documents programmatically without Microsoft Word or interop dependencies. With this library, you can insert a merge field at a bookmark location and execute a mail merge in a Word document using C#.

This enables users to fill Word templates by replacing placeholders with dynamic data, reducing manual editing and improving accuracy.

Steps to insert merge field at a bookmark location in a Word document:

1. Create a new .NET Core console application project.
   
   
2. Install the Syncfusion.DocIO.Net.Core NuGet package as a reference to your project from NuGet.org.
   
   

3. Include the following namespaces in the Program.cs file.
   C#

using Syncfusion.DocIO;
using Syncfusion.DocIO.DLS; 

4. Use the following code example to insert merge field at a bookmark location in a Word document.
   C#

using (FileStream fileStreamPath = new FileStream(Path.GetFullPath(@"Data/Template.docx"), FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
{
    //Load an existing Word document into DocIO instance
    using (WordDocument document = new WordDocument(fileStreamPath, FormatType.Docx))
    {
        #region Insert paragraph at bookmark
        // Create text bodypart
        TextBodyPart bodyPart = new TextBodyPart(document);
        // Create new paragraph and append merge field
        WParagraph para = new WParagraph(document);
        para.AppendField("Product", FieldType.FieldMergeField);
        bodyPart.BodyItems.Add(para);

        //Create the bookmark navigator instance to access the bookmark
        BookmarksNavigator bkmk = new BookmarksNavigator(document);
        //Move the virtual cursor to the location before the end of the bookmark
        bkmk.MoveToBookmark("bookmark");
        // Replace the bookmark content with our body part
        bkmk.ReplaceBookmarkContent(bodyPart);
        #endregion

        #region Execute mailmerge
        string[] fieldNames = { "Product", "ProductNo", "Size" };
        string[] fieldValues = { "Cycle", "1234", "32" };
        document.MailMerge.Execute(fieldNames, fieldValues);
        #endregion

        //Creates file stream
        using (FileStream outputFileStream = new FileStream(Path.GetFullPath(@"Output/Result.docx"), FileMode.Create, FileAccess.ReadWrite))
        {
            //Save the loaded document in WordML format to the output stream
            document.Save(outputFileStream, FormatType.Docx);
            //Close the Word document
            document.Close();
        }
    }
}

You can download a complete working sample to insert merge field at a bookmark location in a Word document from GitHub.

By executing the program, you will get the Word document as follows:

Take a moment to peruse the documentation where you can find basic Word document processing options along with features like mail merge, merge, split, and compare Word documents, find and replace text in the Word document, protect the Word documents, and most importantly, the PDF and Image conversions with code examples.

Conclusion

I hope you enjoyed learning about how to insert merge field at a bookmark location in a .NET Core Word document.

You can refer to our ASP.NET Core DocIO feature tour page to know about its other groundbreaking feature representations and documentation, and how to quickly get started with configuration specifications. You can also explore our ASP.NET Core DocIO example to understand how to create and manipulate data.

For current customers, you can check out our components from the License and Downloads page. If you are new to Syncfusion®, you can try our 30-day free trial to check out our other controls.

If you have any queries or require clarifications, please let us know in the comments section below. You can also contact us through our support forums, Direct-Trac, or feedback portal. We are always happy to assist you!