Remove

MappedDataFieldCollection.Remove method

Removes a field mapping.

public void Remove(string documentFieldName)
ParameterTypeDescription
documentFieldNameStringCase-sensitive name of the mail merge field in the document.

Examples

Shows how to map data columns and MERGEFIELDs with different names so the data is transferred between them during a mail merge.

Document doc = CreateSourceDocMappedDataFields();
DataTable dataTable = CreateSourceTableMappedDataFields();

// The table has a column named "Column2", but there are no MERGEFIELDs with that name.
// Also, we have a MERGEFIELD named "Column3", but the data source does not have a column with that name.
// If data from "Column2" is suitable for the "Column3" MERGEFIELD,
// we can map that column name to the MERGEFIELD in the "MappedDataFields" key/value pair.
MappedDataFieldCollection mappedDataFields = doc.MailMerge.MappedDataFields;

// We can link a data source column name to a MERGEFIELD name like this.
mappedDataFields.Add("MergeFieldName", "DataSourceColumnName");

// Link the data source column named "Column2" to MERGEFIELDs named "Column3".
mappedDataFields.Add("Column3", "Column2");

// The MERGEFIELD name is the "key" to the respective data source column name "value".
Assert.That(mappedDataFields["MergeFieldName"], Is.EqualTo("DataSourceColumnName"));
Assert.That(mappedDataFields.ContainsKey("MergeFieldName"), Is.True);
Assert.That(mappedDataFields.ContainsValue("DataSourceColumnName"), Is.True);

// Now if we run this mail merge, the "Column3" MERGEFIELDs will take data from "Column2" of the table.
doc.MailMerge.Execute(dataTable);

doc.Save(ArtifactsDir + "MailMerge.MappedDataFieldCollection.docx");

// We can iterate over the elements in this collection.
Assert.That(mappedDataFields.Count, Is.EqualTo(2));

using (IEnumerator<KeyValuePair<string, string>> enumerator = mappedDataFields.GetEnumerator())
    while (enumerator.MoveNext())
        Console.WriteLine(
            $"Column named {enumerator.Current.Value} is mapped to MERGEFIELDs named {enumerator.Current.Key}");

// We can also remove elements from the collection.
mappedDataFields.Remove("MergeFieldName");

Assert.That(mappedDataFields.ContainsKey("MergeFieldName"), Is.False);
Assert.That(mappedDataFields.ContainsValue("DataSourceColumnName"), Is.False);

mappedDataFields.Clear();

Assert.That(mappedDataFields.Count, Is.EqualTo(0));

Shows how to map data columns and MERGEFIELDs with different names so the data is transferred between them during a mail merge (CreateSourceDocMappedDataFields).

/// <summary>
/// Create a document with 2 MERGEFIELDs, one of which does not have a
/// corresponding column in the data table from the method below.
/// </summary>
private static Document CreateSourceDocMappedDataFields()
{
    Document doc = new Document();
    DocumentBuilder builder = new DocumentBuilder(doc);

    builder.InsertField(" MERGEFIELD Column1");
    builder.Write(", ");
    builder.InsertField(" MERGEFIELD Column3");

    return doc;
}

/// <summary>
/// Create a data table with 2 columns, one of which does not have a
/// corresponding MERGEFIELD in the source document from the method above.
/// </summary>
private static DataTable CreateSourceTableMappedDataFields()
{
    DataTable dataTable = new DataTable("MyTable");
    dataTable.Columns.Add("Column1");
    dataTable.Columns.Add("Column2");
    dataTable.Rows.Add(new object[] { "Value1", "Value2" });

    return dataTable;
}

See Also

MappedDataFieldCollection.GetEnumerator