Sounds like you really want a Dictionary<int, string>
or possibly a switch
statement...
You can do it with the conditional operator though:
userType = user.Type == 0 ? "Admin"
: user.Type == 1 ? "User"
: user.Type == 2 ? "Employee"
: "The default you didn't specify";
While you could put that in one line, I'd strongly urge you not to.
I would normally only do this for different conditions though - not just several different possible values, which is better handled in a map.