How to merge outer group fields within an inner nested group using nested mail merge in a 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 merge outer group fields within an inner nested group using nested mail merge in a Word document using C#.

To create a proper template document, refer to the image structure below. To use the data from a corresponding group or table in another group or table, follow the highlighted format (GroupName:FieldName) to access the data.

Steps to merge outer group fields within an inner nested group using nested 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.DLS;
using Syncfusion.DocIO; 

4. Use the following code example to merge outer group fields within an inner nested group using nested mail merge in a Word document.
   C#

using (FileStream fileStream = new FileStream(Path.GetFullPath(@"Data/Template.docx"), FileMode.Open, FileAccess.ReadWrite))
{
   //Open the template Word document.
   using (WordDocument document = new WordDocument(fileStream, FormatType.Docx))
   {
       //Create the commands which contain the queries to get the data from the dataset.
       ArrayList commands = new ArrayList();
       commands.Add(new DictionaryEntry("Bills", ""));
       commands.Add(new DictionaryEntry("ProductDetails", "BillId = %Bills.BillId%"));
       commands.Add(new DictionaryEntry("Price", "DetailID = %ProductDetails.DetailID%"));
       //Create the data set that contains data to perform the mail merge.
       DataSet dataSet = GetDataSet();
       //Remove groups that contain empty merge fields. 
       document.MailMerge.RemoveEmptyGroup = true;
       //Remove paragraphs that contain empty merge fields. 
       document.MailMerge.RemoveEmptyParagraphs = true;
       //Execute the nested mail merge.
       document.MailMerge.ExecuteNestedGroup(dataSet, commands);
       //Create a file stream.
       using (FileStream outputStream = new FileStream(Path.GetFullPath(@"Output/Result.docx"), FileMode.Create, FileAccess.ReadWrite))
       {
           //Save a Word document to the file stream.
           document.Save(outputStream, FormatType.Docx);
       }
   }
}

5. Use the following code example to create a data set to perform the mail merge.
   C#

private static DataSet GetDataSet()
{
   DataSet ds = new DataSet();
   DataTable table = new DataTable("Bills");
   table.Columns.Add("BillID");
   table.Columns.Add("ControlNumber");
   table.Columns.Add("RecipientId");
   table.Columns.Add("Picture", typeof(byte[]));
   DataRow row = table.NewRow();
   table.Rows.Add(row);
   row["BillID"] = "BL7936";
   row["ControlNumber"] = "CN100";
   row["RecipientId"] = "900893674";
   FileStream fs = new FileStream((@"Data/Mountain-300.png"), FileMode.Open, FileAccess.Read);
   byte[] buff = new byte[fs.Length];
   fs.Read(buff, 0, buff.Length);
   fs.Dispose();
   row["Picture"] = buff;
   ds.Tables.Add(table);

   table = new DataTable("ProductDetails");
   table.Columns.Add("BillID");
   table.Columns.Add("DetailID");
   table.Columns.Add("ControlNumber");
   table.Columns.Add("ProductAmount");
   table.Columns.Add("Picture", typeof(byte[]));
   row = table.NewRow();
   table.Rows.Add(row);
   row["BillID"] = "BL7936";
   row["DetailID"] = "6758671";
   row["ControlNumber"] = "CN110";
   row["ProductAmount"] = "1500";
   fs = new FileStream((@"Data/Road-550-W.png"), FileMode.Open, FileAccess.ReadWrite);
   buff = new byte[fs.Length];
   fs.Read(buff, 0, buff.Length);
   fs.Dispose();
   row["Picture"] = buff;
   ds.Tables.Add(table);

   table = new DataTable("Price");
   table.Columns.Add("DetailID");
   table.Columns.Add("ControlNumber");
   table.Columns.Add("DiscountAmount");
   table.Columns.Add("Picture", typeof(byte[]));
   row = table.NewRow();
   table.Rows.Add(row);
   row["DetailID"] = "6758671";
   row["ControlNumber"] = "CN111";
   row["DiscountAmount"] = "500";
   fs = new FileStream((@"Data/Mountain-200.png"), FileMode.Open, FileAccess.ReadWrite);
   buff = new byte[fs.Length];
   fs.Read(buff, 0, buff.Length);
   fs.Dispose();
   row["Picture"] = buff;
   ds.Tables.Add(table);
   return ds;
} 

You can download a complete working sample to merge outer group fields within an inner nested group using nested mail merge from the GitHub.

Template Word document

Generated result document

Take a moment to peruse the documentation where you can find basic Word document processing options along with the 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.

See Also

• Mail merge for nested groups

Conclusion

I hope you enjoyed learning about how to merge outer group fields within an inner nested group using nested mail merge in .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 for 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!