advent button sending two fields into one field

[Schammy]

I'm am brand new to the filemaker and rusty on programming. I want to make a button on a form take two of the fields 'firstname' and 'lastname' send it into another field 'firstlastname' for another forms popdown menu.

or upon entry send the two fields to 'firstlastname'.

Thank you

[Fitch]

Set the auto enter options for 'firstlastname' to:

firstname & " " & lastname

[Schammy]

Thank you. Filemaker is awesome.