How to check if a variable is loaded in JavaScript?

Question

How do I see if a certain object has been loaded, and if not, how can it be loaded, like the following?

if (!isObjectLoaded(someVar)) {
    someVar= loadObject()         


        

Answer 1

You probably want to see if a given object is defined

Especially if its done in an asynchronous thread with a setTimeout to check when it turns up.

  var generate = function()
  { 
      window.foo = {}; 
  }; 
  var i = 0;
  var detect = function()
  {
     if( typeof window.foo == "undefined" ) 
     {
           alert( "Created!"); 
           clearInterval( i );
     }
   };
   setTimeout( generate, 15000 ); 
   i = setInterval( detect, 100 ); 

should in theory detect when window.foo comes into existance.