Use Expressions In Design Mode

Expressions are conditions or functions that applications evaluate to produce specific types of values. You can use expressions to define conditions such as rules, input constraints, and preconditions. The Page expression form is of the same record type as the page. The expression loads no user interface up front with the page itself, just pieces of data for use in expressions elsewhere on the page.

Warning: Working with expression requires some knowledge of SQL.

Expressions leverage the full VB.NET syntax. For example, to change the constituent page caption to include the constituent name and the date/time stamp, you would use the following expression:

=Fields!NAME & “ “ & date.now

The fields included in the Available Fields box of the Expression screen are determined by the ExpressionDataForm.

  1. From the properties screen select “Expression” in the drop-down menu. An Expression field appears on the properties screen.

    For example, you can change the Accounts tab in a constituent record. Currently the tab uses a “PageContext” ContextType, but you want to create an expression and assign it as the ContextType:

    1. From the Accounts tab, select the Properties button that displays on the tab when you activate Design Mode.

    2. In the ContextType field, select the drop-down menu and select “Expression.” The Expression field appears in the properties screen under the ContextType field.

      Note: For information about how to activate Design Mode, see Activate Design Mode.

  2. Select the ellipsis at the end of the Expression field. The Expression screen appears.

  3. The Available Fields pane displays all available expression description types. Compose your expression in the Expression pane. Double select on any field listed in the Available Fields pane to move the field into the Expression pane.

    Note: The fields included in the Available Fields box of the Expression screen are determined by the ExpressionDataForm.

  4. Select OK. You return to the properties screen.

  5. Select Save. You return to the program page.