The TXTextControl.DocumentServer.MailMerge.FieldMerged event returns useful information and options to manipulate the merged content in the TXTextControl.DocumentServer.MailMerge.FieldMergedEventArgs class.

Since version X14 (24.0), the TXTextControl.DocumentServer.MailMerge.FieldMergedEventArgs.TableCell property returns a TXTextControl.TableCell class in case the merge field is positioned inside a table. This can be used to manipulate the table cell based on merged values.

Consider the following data structure and instance that is used to merge a template:

public class Report
{
    public Row[] Rows { get; set; }
}

public class Row
{
    public int Value { get; set; }
    public string Name { get; set; }
}

Report report = new Report()
{
    Rows = new Row[] {
        new Row() { Name = "Row0", Value = 10 },
        new Row() { Name = "Row1", Value = 100 },
        new Row() { Name = "Row2", Value = 200 },
        new Row() { Name = "Row3", Value = 300 },
        new Row() { Name = "Row4", Value = 400 },
        new Row() { Name = "Row5", Value = 500 },
        new Row() { Name = "Row6", Value = 600 },
        new Row() { Name = "Row7", Value = 700 },
    }
};

reports = new List<Report>() { report };

The following code creates a new instance of the reporting engine TXTextControl.DocumentServer.MailMerge class, attaches the FieldMerged event and calls the TXTextControl.DocumentServer.MailMerge.MergeObjects method to merge a template with the created data object.

using (MailMerge mailMerge = new MailMerge())
{
    mailMerge.TextComponent = textControl1;
    mailMerge.FieldMerged += mailMerge_FieldMerged;

    mailMerge.MergeObjects(reports);
}

In the FieldMerged event, the field value is parsed and mapped to a color based on the value range. Accordingly, the background color of the outer table cell is highlighted.

private void mailMerge_FieldMerged(object sender, MailMerge.FieldMergedEventArgs e)
{
    if (e.TableCell == null)
        return;

    if (e.MailMergeFieldAdapter.TypeName == MergeField.TYPE_NAME)
    {
        MergeField mergeField = e.MailMergeFieldAdapter as MergeField;
        Color cellColor;
        int value;

        if (int.TryParse(mergeField.Text, out value) == true)
        {
            if (value >= 700)
                cellColor = Color.Red;
            else if (value >= 600)
                cellColor = Color.Orange;
            else if (value >= 500)
                cellColor = Color.Yellow;
            else if (value >= 400)
                cellColor = Color.Green;
            else if (value >= 300)
                cellColor = Color.Blue;
            else if (value >= 200)
                cellColor = Color.Indigo;
            else if (value >= 100)
                cellColor = Color.Violet;
            else
                cellColor = e.TableCell.CellFormat.BackColor;

            e.TableCell.CellFormat.BackColor = cellColor;
        }
    }
}

The following screenshot shows the results of this merge process:

This is just one of many ideas what to do with the flexible reporting framework MailMerge to customize the merging process.