Accessing the Expression Editor
The Expression Editor is accessed from within the Properties section for specific relevant properties. To open the Expression Editor, click on its icon, as indicated below, or select it from a field’s associated drop-down list:
Layout of the Expression Editor
The Expression Editor is composed of the following:
Enter an expression or select relevant variables and functions from the available lists to build up an expression.
Variables and Functions
- To expand a list, click on the expander control element:
- To select a variable or function, double-click on it. (The selected variable or function is then added to the Expression area.)
To view help for a specific function, click on it where it is listed. The Help for the selected function is displayed in the help section.
To test an expression for correct structure and syntax:
Click on the Test tab
Click the Run Test button
The result of the test is displayed
- A typical error message is: “Expression contains invalid syntax.”
When testing an expression, usually relevant input has to be provided by the user. If the expression references an output from a function above, a value needs to be provided that will substitute the output in the expression. The test will be executed with that value. If my expression is Integer1 + Integer2, then the user will be asked to provide two integers in the test tab for the test.