TextField Query

Hi there,

I've got the following script

 #pragma strict
 var stringToEdit : String = "Type Code Here";
 
 function OnGUI(){
 
     stringToEdit = GUI.TextField (Rect (10, 10, 200, 20), stringToEdit, 25);;
     
     if (GUI.Button (Rect(Screen.width/2,Screen.height/2,80,20), "Submit")){
     
     if(stringToEdit == "LCD TV"){
         Application.LoadLevel ("TVscene");
     }
     if(stringToEdit == "Camera"){
         Application.LoadLevel ("Camerascene");
     }
         
         }
         }

Which works great. However, if the user types in something in the textfield that isn't specified in the code, I want some sort of error message to come up (i.e. "Error: Invalid Keyword"). Could I achieve this with an else statement perhaps?

Anyone have any ideas?

Thanks