Crystal Reports combine fields in string formula, one field no data -

i given formula:

if not (isnull({person.last_name}))  {person.last_name}+","+" "+{person.first_name} else  "no name" 

this formula seems work fine need add field {person.middle_name} when write formula

if not (isnull({person.last_name}))  {person.last_name}+","+" "+{person.first_name}+","+" "+{person.middle_name} else  "no name" 

if person has middle name, looks fine. if person not have middle name , there no data in field, report shows no information @ all.

apologies beginner question, , thank in advance.

you can nest additional if statement evaluate middle name. break criteria multiple formulas. create separate formula fname, lname, mname. each have if statement similar above (if isnull({mname} "" else {mname}).

then can create additional formula concatenate them {lastname} + {firstname} + {middlename}