Checking if an actor has an item is simple with the latest version of trigedit. has_item() can search via vnum or keyword.
Code:
Name: 'Check for treats - 207',  VNum: [  155], RNum: [  155]
Trigger Intended Assignment: Mobiles
Trigger Type: Greet , Numeric Arg: 100, Arg list: None
Commands:
* By Rumble of The Builder Academy    tbamud.com 9091
* My dog is looking if people have some beggin strips.
if %actor.has_item(164)%
  wait 1 sec
  %send% %actor% %self.name% sits down and stands up on %self.hisher% hind legs, then starts whining pitifully staring at you.
  %echoaround% %actor% %self.name% sits down and stands up on %self.hisher% hind legs, then starts whining pitifully staring at %actor.name%.
* Or if they have her rubber chicken.
elseif %actor.has_item(172)%
  wait 1 sec
  emote sniff %actor.name%
  wait 1 sec
  growl %actor.name%
  %send% %actor% %self.name% tries to get at something you are carrying.
  %echoaround% %actor% %self.name% tries to get at something %actor.name% is carrying.
end
 
On older versions of trigedit you had to do a lot more work. But, it is a good example of how to use a loop to look
through a players inventory, equipment, and containers.
Code:
Name: 'Mob Checks Player Inventory',  VNum: [   32], RNum: [   32]
Trigger Intended Assignment: Mobiles
Trigger Type: Greet , Numeric Arg: 100, Arg list: None
Commands:
* By Rumble of The Builder Academy    tbamud.com 9091
* This trigger has been replaced by the has_item variable. But this is still a
* good example. if %actor.has_item(1300)% does the same thing.
if %actor.eq(wield)%
  eval wep %actor.eq(wield)%
  if %wep.vnum%==1300
    set has_it 1
  end
end
* Checks the actors inventory if not wielding it.
if !%has_it%
  eval i %actor.inventory%
  while %i%
    set next %i.next_in_list%
    if %i.vnum%==1300
      set has_it 1
      break
    end
    * checks inside containers
    if %i.type% == CONTAINER
      while %i.contents%
        if %i.contents.vnum%==1300
          set has_it 1
          break
        end
      done
    end    
    set i %next%
  done
end
*
if %has_it%
  say %actor.name% has that special item.
else
  say %actor.name% doesnt have that crappy item.
end
 
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