Expression

Expressions are used to calculates values or compose strings with Form Control Expressions. Expressions only show values but cannot be modified by the Users. However, the content of Expression can be stored in Attributes or Variables, if the expression is backed by one. Expressions can also be hidden, so that Users do not see their result in the Form, but the result is just stored.

Control properties

• Id / Name - Identifier of the Form Control. Id / Name needs to be unique for all Form Controls on the same Form. Id / Name also binds the Form Control to an Attribute with the same name of the Variable backing the From. This means that the Form Control will load and show the value from said Attribute when the Form is entered, and that the value of the Form Control is stored in the Attribute when the Form is left by a Save or Sign and Save action. The Form Control can also be bound to an Attribute of a Variable other than the one backing the From by using the fully qualified name as Id / Name:

  • VariableName.AttributeName - Binds the Form Control to an Attribute of a Entity or Variable
  • ContextVariableName.ContextVariableName - Binds the Form Control to a Context Variable that holds only one value without any Attributes

  A detailed explanation of the different linking mechanisms between a Form Control and an Attribute is given in the Variable and Variable Type configuration of the From Activity.

• Label text - Caption rendered above the Form Control thus identifying it to the Users.

• Help text - Explanation of the Form Control shown below the Form Control.

• Value expression - Processes Control Expression calculating the value or composing the string of the Form Control.

• Hide control? - Hides (Yes) or shows (No) the Form Control in the Form. Be aware that the content of hidden Form Controls is stored by Save and Sign and Save Actions in the linked Attribute.