FieldMergingArgs class

Provides data for the MergeField event.

To learn more, visit the Mail Merge and Reporting documentation article.

public class FieldMergingArgs : FieldMergingArgsBase


Document { get; }Returns the Document object for which the mail merge is performed.
DocumentFieldName { get; }Gets the name of the merge field as specified in the document.
Field { get; }Gets the object that represents the current merge field.
FieldName { get; }Gets the name of the merge field in the data source.
FieldValue { get; set; }Gets or sets the value of the field from the data source.
RecordIndex { get; }Gets the zero based index of the record that is being merged.
TableName { get; }Gets the name of the data table for the current merge operation or empty string if the name is not available.
Text { get; set; }Gets or sets the text that will be inserted into the document for the current merge field.


The MergeField event occurs during mail merge when a simple mail merge field is encountered in the document. You can respond to this event to return text for the mail merge engine to insert into the document.


Shows how to execute a mail merge with a custom callback that handles merge data in the form of HTML documents.

public void MergeHtml()
    Document doc = new Document();
    DocumentBuilder builder = new DocumentBuilder(doc);

    builder.InsertField(@"MERGEFIELD  html_Title  \b Content");
    builder.InsertField(@"MERGEFIELD  html_Body  \b Content");

    object[] mergeData =
        "<html>" +
            "<h1>" +
                "<span style=\"color: #0000ff; font-family: Arial;\">Hello World!</span>" +
            "</h1>" +

        "<html>" +
            "<blockquote>" +
                "<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.</p>" +
            "</blockquote>" +

    doc.MailMerge.FieldMergingCallback = new HandleMergeFieldInsertHtml();
    doc.MailMerge.Execute(new[] { "html_Title", "html_Body" }, mergeData);

    doc.Save(ArtifactsDir + "MailMergeEvent.MergeHtml.docx");

/// <summary>
/// If the mail merge encounters a MERGEFIELD whose name starts with the "html_" prefix,
/// this callback parses its merge data as HTML content and adds the result to the document location of the MERGEFIELD.
/// </summary>
private class HandleMergeFieldInsertHtml : IFieldMergingCallback
    /// <summary>
    /// Called when a mail merge merges data into a MERGEFIELD.
    /// </summary>
    void IFieldMergingCallback.FieldMerging(FieldMergingArgs args)
        if (args.DocumentFieldName.StartsWith("html_") && args.Field.GetFieldCode().Contains("\\b"))
            // Add parsed HTML data to the document's body.
            DocumentBuilder builder = new DocumentBuilder(args.Document);

            // Since we have already inserted the merged content manually,
            // we will not need to respond to this event by returning content via the "Text" property. 
            args.Text = string.Empty;

    void IFieldMergingCallback.ImageFieldMerging(ImageFieldMergingArgs args)
        // Do nothing.

See Also