Initializing a Variable
Define an initial value for a process variable by creating an expression, literal document, or copying a value from a variable. Select the dialog button to generate data for a complex variable.
All variables must be initialized before use. A variable, or part of a variable, can be initialized in several ways, including receiving a message in an activity, assigning data in an assign or input mapping, or adding an initial value to the variable definition.
Variables in receive, onMessage, onEvent, and inbound invoke activities are automatically initialized. You can initialize other process variables when you declare them. Doing so allows you to skip an assign activity that would initialize a variable.
The initial value of a variable is validated against the schema or WSDL definition during process execution. You can also validate the variable by adding it to a validate activity. For details, see Validating Variables.
To add an initial value to a variable:
- 1. Add a new process variable, as described in Adding a Variable.
- 2. From the Outline or Process Variables View, select a variable.
- 3. In the Properties view, select the Dialog (...)) Button next to Initial Value.
- 4. In the Variable Initialization dialog, select the details for assigning a value to the variable. The selections are the same as those in the From side of a copy operation. For explanations of the From Type and related attributes, see Assign.
For a variable that is declared in a scope that contains a start activity, such as a Receive, you must not initialize the variable with a value that can change, such as a date-time function. This restriction allows for a pre-computed value for all process instances.