The Expression Builder dialog box helps you develop an expression by displaying field names, attachments, workflow groups, XML data fields, system fields, and partner links for you to select. In addition, if functions are appropriate in the expression, you can choose the appropriate function and this dialog box displays the function name and syntax, as well as providing access to the online Help.
To access the Expression Builder dialog box, click Expression Builder in any field where an expression is permitted.
The name of the item for which you are building the expression displays in the title bar of the window. Build the expression in the expression area by inserting the names of existing fields and operators, and by typing directly in the expression area.
To use the names of data fields, attachments, workflow groups, XML data fields, and other items either defined in this workflow or inherited from a parent workflow
To use Guid Fields in the expression
To use Partner Links in the expression
If you are invoking web services in a workflow, you might want to modify the header of the invoking message at runtime to either invoke a different web service than the one defined in the partner link, or to pass a user name and password to a web service that requires authentication.
Note that you must modify the expression to make it a valid string. That means that you must add double-quotes at the beginning and end of the string, and before any existing double-quotes.
For example workflows demonstrating how to modify the partner link header, see examples 5 and 7 in Web Services examples.
To use functions in the expression
To define an expression for an attachment
To define an expression for a workflow group
When you browse for a document, folder, file name, or a user or group name, the selected item is inserted into the expression area in the format required by workflow system.
You can also assign a user to a workflow group using one of the following:
For example, if WfGroupA is the participant for the third step in the workflow and you want user number 50 to process that step, enter the following on the Assignment tab of a previous step in the workflow. Note that @50 is assigned to the first element of the workflow group.
Field name | Expression |
---|---|
WfGroupA[1] | "@50" |
In the following example entry on the Assignment tab, the userstring data field holds the participant name.
Field name | Expression |
---|---|
WfGroupA[1] | "@userstring" |
Use the following syntax on the Assignment tab (After Completion) to assign the numeric ID of the participant at the current step to an element in a workflow group that will process a subsequent step.
Field name | Expression |
---|---|
WfGroupA[1] | "@"+numbertostring(F_BoundUser) |
Since the @ symbol has a special meaning in specifying a participant name in a workflow, you should observe the following rule for using the @ symbol in user names:
The system will correctly route work to participants with user names of @123abc or @abc123 since these names contain both letters and numbers.