this in javascript

Question

I\'m having a confusing problem using \'this\' in javascript. I have a method \'get_data\' which returns me some member variable of an object. Sometimes it returns to me the o

Answer 1

What 'this' is in JavaScript depends on how you call the function. If 'this' is not bound to an object, this will be the window object.

If you call

item = new Feed_Item()
item.foo() //foo will be called with correct 'this'

But if you do Feed_Item(some_data), you will add a couple of functions to the global window object.

There are a lot of articles explaining this, e.g. http://www.digital-web.com/articles/scope_in_javascript/