Add a new CustomField based on RegExpTextCFType (Regular Expression CustomField).
Specify its name and its description.
You are able to manage it.
- In which Screen it will be available.
- Configure its RegExp Pattern.
In Configure CutomField screen, you have to define a Default Value as Regular Expression Pattern.
You are able to configure a Pattern following Java specifications.
Note that the Pattern validation is done on Javascript side too, for which its specifications do not cover all Java specifications.
You are ready to use the RegExp field in your screens and have a validation on the Client side.
You may also use the RegExp Validator for your Transition Screens,
but also in the Edit transition using the Issue Validation provided by the Minyaa Workflow plugin.