Tracing the length of an associative array?

This should be an easy one for you guys.
I haven’t doen this in so long I forget how its done…

Ok, so I got an assocaitive object array like this:
myArray = new Object();
myArray[0] = {item:“item1”, price:"$1.99", active:0};
myArray[1] = {item:“item2”, price:"$1.99", active:0};
myArray[2] = {item:“item3”, price:"$1.99", active:0};

Now, how do I track the length of this object array.

I would have thought it was:

But thats not the solution.
Any ideas?