Assign username on registration last name first initial

Hello, I have found a few similar questions but need further guidance to get a solution working. Similar to this, but not using CB Connect www.joomlapolis.com/forum/255-developer-members-support/234372-set-username-on-registration-as-firstname-user-id

I am building a site with CB & CB Subs where users will register and be assigned a username. Their username will be their last name, first initial, and if that exists, add a number (beginning with 2). For instance:

John Smith = smithj
James Smith = smithj2
Joseph Smith = smithj3

I am not sure how to get just the first letter of first name, and how to add the incremented number. I would love to show the generated username on the registration page to the user, but less important as long as they get the login.

Please advise. Thank you!

Only way to do that is with CB Auto Actions acting on the after registration trigger with a Code action that modifies the username. Alternatively you can try doing it with a database query in a Query action. Both should allow you to detect existing username and increment as needed, but both will require you to code these usages.

Thanks for the response. It doesn't sound too hard to set up an auto action, but I'm not sure how to just get the first letter from the first name.

I'll do some reading up on the plugin's general usage but if you're able to advise on this particular part (or the use case) I would also appreciate that.

Thanks again,
Jeff

CB Auto Actions comes with format functions, which you can enable under the parameters tab. One of them will let you grab the first letter of the firstname using the below for example.

[cb:parse function="extract" length="1"][firstname][/cb:parse]