How to Modify the Font During Mail Merge in Core Word Document?

Syncfusion® Essential® DocIO is a .NET Word library used to create, read, edit, and convert Word documents programmatically without Microsoft Word or interop dependencies. Using this library, you can modify the font during a mail merge in a Word document using C#.

Steps to modify the font during a mail merge 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 Program.cs file
   C#

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

4. Use the following code example to modify the font during a mail merge.
   C#

using (FileStream fileStream = new FileStream(Path.GetFullPath(@"Data/Template.docx"), FileMode.Open, FileAccess.ReadWrite))
{
   //Opens the template document.
   using (WordDocument document = new WordDocument(fileStream, FormatType.Docx))
   {
       //Uses the mail merge events to perform the conditional formatting during runtime.
       document.MailMerge.MergeField += new MergeFieldEventHandler(ModifyFont);
       //Executes Mail Merge with groups.
       document.MailMerge.ExecuteGroup(GetDataTable());
       //Creates file stream.
       using (FileStream outputStream = new FileStream(Path.GetFullPath(@"Output/Result.docx"), FileMode.Create, FileAccess.ReadWrite))
       {
           //Saves the Word document to file stream.
           document.Save(outputStream, FormatType.Docx);
       }
   }
}

5. Use the following event handling method that handle the MergeField event.
   C#

/// <summary>
/// Represents the method that handles the MergeField event.
/// </summary>      
private static void ModifyFont(object sender, MergeFieldEventArgs args)
{
   // Sets the font name to Arial for the selected text range.
   args.TextRange.CharacterFormat.FontName = "Arial";
   // Sets the font size to 18 points for the selected text range.
   args.TextRange.CharacterFormat.FontSize = 18;
   // Applies bold formatting to the selected text range.
   args.TextRange.CharacterFormat.Bold = true;
   // Applies italic formatting to the selected text range.
   args.TextRange.CharacterFormat.Italic = true;
   // Applies single underline to the selected text range.
   args.TextRange.CharacterFormat.UnderlineStyle = UnderlineStyle.Single;
}

6. Use the following helper method to retrieve the data for performing the mail merge.
   C#

/// <summary>
/// Gets the data to perform mail merge.
/// </summary>
private static DataTable GetDataTable()
{
   // Creates a new DataTable with the name "Employee".
   DataTable dataTable = new DataTable("Employee");
   // Adds a column "EmployeeName" to the DataTable.
   dataTable.Columns.Add("EmployeeName");
   // Adds a column "EmployeeNumber" to the DataTable.
   dataTable.Columns.Add("EmployeeNumber");

   // Loops 20 times to add rows to the DataTable.
   for (int i = 0; i < 20; i++)
   {
       // Creates a new DataRow for the DataTable.
       DataRow datarow = dataTable.NewRow();
       // Adds the newly created DataRow to the DataTable.
       dataTable.Rows.Add(datarow);
       // Sets the value of the first column (EmployeeName) for the current row.
       datarow[0] = "Employee" + i.ToString();
       // Sets the value of the second column (EmployeeNumber) for the current row.
       datarow[1] = "EMP" + i.ToString();
   }
   // Returns the populated DataTable.
   return dataTable;
}

You can download a complete working sample to modify the font during a mail merge in a Word document from GitHub.

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

Conclusion
I hope you enjoyed learning about how to modify the font during mail merge in 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 for configuration specifications. You can also explore our ASP.NET Core DocIO example to understand how to create and manipulate data.

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