using Nintex WorkflowDesigner in SharePoint 2016, I created a workflow which starts up showing a Nintex StartForm (accessible by selecting "Workflow Settings", then "edit StartForm" in the workflow's top menu). Within this StartForm, I use a WebQuery to access a certain column of the selected document (the document the workflow was started with). The ServiceUrl of the WebQuery holds the following content (bold text portions are references to available variables):
The "Subject" reference string thus holds a value of the respective document's column and is used to build the name of a SiteGroup. From this SiteGroup, the users are to be displayed within a DropDownList within the StartForm. This works fine so far, when the "Subject" variable holds exactly ONE string and the respective SiteGroup is identified. So, the members are displayed within the StartForm.
Now, as the "Subject" variable might hold multiple values (not just one as described above), the string assembly "SubjectGroup" will fail as soon as there have been set multiple values within. In this case, no valid SiteGroup will be found. So, in order to allow the "Subject" variable (that is column value of my document) to hold multiple values, I want to pre-process the variable BEFORE it reaches the ServiceUrl field of my WebQuery.
Is there a way to do arbitrary calculations at start of a workflow BEFORE the StartForm is displayed?
I've seen, there are "Workflow Variables" available within the StartForm, but I don't know how I could set them BEFORE the StartForm shows.
Thanks for any hint.