Adding a DataWindow expression opens the Modify Expression dialog box. This enables you to create references to columns from the data source of the DataWindow object. One use of this feature is to return a fragment of XML to embed, providing another level of dynamic XML generation.
If you use a control reference or a DataWindow expression that does not include
a string to represent Date and DateTime columns in a template, the XML
output conforms to ISO 8601 date and time formats. For example, consider
a date that displays as 12/27/2004 in
the DataWindow object, using the display format mm/dd/yyyy.
If the export template does not use an expression that includes
a string, the date is exported to XML as 2004-12-27.
However, if the export template uses an expression that combines a column with a Date or DateTime datatype with a string, the entire expression is exported as a string and the regional settings in the Windows registry are used to format the date and time.
Using the previous example, if the short date format in the
registry is MM/dd/yy,
and the DataWindow expression is: "Start Date is " + start_date,
the XML output is Start Date is 12/27/04.
