Extract alphanumeric strings in an intent

[Kevin MacDermid]

I've been digging around a bit and I can't figure out how to extract alphanumeric strings in intents as entities. In my case users are likely to give me a model or part number that is a combination of characters and digits.

I tried detecting them using a regex like '\w*\d+\w*', but in most cases I get an error in the entity interface that says that the Regex is too broad. I guess I could do a similar regex in a Webhook but that seems like kind of a nasty workaround. Is there a proper way to handle that sort of entity?

[Axel Eduardo Murillo]

With Regex Entities, you can extract your intended alphanumeric values using the following: 

1. Set your regex entity entry to ‘\s\w*\d+\w*\s‘. 

2. Add your regex to an intent’s training phrase:

   1. Example: 
      

If you wish to capture the regex on a form parameter, use the following:

1. Set your regex entity entry to ‘^\w*\d+\w*$’.

2. Set up your agent to prompt the user into entering only the alphanumeric value:

   1. Example: 

For similar regex entries, please utilize the ‘^’ and ‘$’ specifiers. These make it clear that the entity is to be checking if the whole query matches, and sufficiently resolves the “regex is too broad” error. 

You can add both ‘\s\w*\d+\w*\s‘ and ‘^\w*\d+\w*$’ as entries to the EntityType to cover both situations. Be sure to check the Dialogflow documentation for further tips. You can also check the Regular Expression Syntax documentation.