Conditions and Statements in the UI Designer are built using Expressions. Expressions are created by combining operators, functions, and values. When eCASE executes the rules in a form, the rules engine calculates the results of Expressions. The Expression Editor provides an interface for generating and modifying Expressions.
When you open the Expression Editor, note the Select From List drop-down. Here you will be able to see all the fields from your form, as well as the operators and functions available in the UI Designer. Clicking one of the options in the list inserts it in the expression wherever your cursor is located, and can help avoid syntax errors.
If you need to use a constant number in your expression, it can be entered with the keyboard.
If you need to use a constant string, it must be placed inside of quotes (“”). If you need your custom string to contain multiple lines, you can insert a new line character with the sequence “`n” (the ` is the one that appears on the key with ~).
It is important to keep the following in mind:
Rules on a single value field are allowed to affect any type of fields in one Case Type, while rules on multiple value fields are only allowed to affect single value fields and other multiple value fields in their group.
Rules always follow their field. If a control is not bound to a field, it will not inherit any rule from the field. As long as the field is in the data model of the form, the rules are kept and stored under the field.
Rules are not always synced with a field. If the field is removed from the data model and if this field is used by some other rules, a prompt appears asking users to change existing rules.
If a field is used by some rules, the binding of this field cannot be changed unless all the rule sets that have this field are removed.