当有明确的值时，为什么这些数据显示未定义？

Question

On my page, I'm logging this:

console.log(self);
console.log(self.data.events);

The self is showing data, however self.data.events is showing undefined , how am I referencing this wrong?

Answer 1

but why is console.log(self.data) working but not console.log(self.data.events)?

As @Nick Parsons hinted in his comment, it might be because console.log behaves asynchronously in some browsers and will not log a "snapshot" at the time it was logged but will reflect updates on whatever is referenced, in this case self.data (which is initially defined as an empty object!)...

I have a feeling that @Dinesh Kumar's comment is on the right track, you're calling these functions after each other:

self.load_event_data();
self.load_zip_codes();
self.bind_events();
self.handle_filter_params();
self.cluster();

the issue is within self.cluster() but it is possible that the AJAX call you're making in self.load_event_data() is not be done yet when self.cluster() is called, so I'd suggest you try and call self.cluster() from within self.load_event_data() whenever you got data updated with the events.