Sets the MailMerge's data source to a two-dimensional (rectangular) array of objects. A MailMerge by default treats the page content as a repeat block, repeating the page content for each row unless NEXT fields are used. If the WordTemplate.EnableNEXTFields property is set to true, the NEXT field can also be used to indicate that the next row of data should be inserted instead of the current row at the next occurence of the merge fields. This should largely imitate the behavior of a Microsoft Word Mail merge.

 public void SetMailMerge(System.Object[][] jaggedArray, System.String[] columnNames)
Public Sub SetMailMerge(ByVal jaggedArray As Object()(), ByVal columnNames As String())

The jagged array (array-of-arrays) to use as the data source.

The one-dimensional array of strings that represent the field names to be replaced by the data. These names must match the column names from your data source.

Save will throw this exception if null (C#) or Nothing (VB.NET) is passed to the method.

You can call SetMailMerge once for each instance of WordTemplate. If you are using the Word 2003 binary template file type (.doc/.dot), you can call SetMailMerge or SetRepeatBlock, but not both.

Additionally, only the page content is repeated for each row, not the entire page itself. If you wish to have the page itself repeat for each row, you will need to remember to place a page break at the bottom of the page.  Alternatively, you can create a hidden page break at the top of the page as follows:

  • Put the cursor at the top of the document
  • Go to Page Layout and open the paragraph formatting dialog
  • On the Line and Page Breaks tab,  select "Page Break Before"

Merge Fields for using the SetMailMerge method must not specify a data source – the data source is implied, and using a data source name will cause WordTemplate to throw an error. Valid merge field formats for use with SetMailMerge include field names («fieldname») and field ordinals («#1»).

SetMailMerge will now work with headers and footers. A section break is required instead of a page break if each header or footer will be different.

          //--- A 2-D jagged array of values
          object[][] data = new object[][]{
               new string[]{"Knoxville","Tennessee"},
               new string[]{"Boston","Massachusetts"},
               new string[]{"Washington","DC"},
               new string[]{"Seattle","Washington"},
               new string[]{"Chicago", "Illinois"},
               new string[]{"New York","New York"},
               new string[]{"Atlanta", "Georgia"},
               new string[]{"Los Angeles", "California"},
               new string[]{"Houston", "Texas"}

          //--- Names array, elements correspond to merge field names
          string[] names = new string[]{"City", "State"};
          WordTemplate wt = new WordTemplate();

          //--- Set the mail merge
          //--- The data source is the 2-D jagged data array
          wt.SetMailMerge(data, names);
          wt.Save(Page.Response, "output.doc", false);

          '--- A 2-D jagged array of values
          Dim data()() As Object = { _
               New Object() {"Knoxville", "Tennessee"}, _
               New Object() {"Boston", "Massachusetts"}, _
               New Object() {"Washington", "DC"}, _
               New Object() {"Seattle", "Washington"}, _
               New Object() {"Chicago", "Illinois"}, _
               New Object() {"New York", "New York"}, _
               New Object() {"Atlanta", "Georgia"}, _
               New Object() {"Los Angeles", "California"}, _
               New Object() {"Houston", "Texas"} _

          '--- names array, elements correspond to merge field names
          Dim names() As String = {"City", "State"}
          Dim wt As New WordTemplate()

          '--- Set the mail merge
          '--- The data source is the 2-D jagged data array
          wt.SetMailMerge(data, names)
          wt.Save(Page.Response, "output.doc", False)