How Does AJAX work

Question

I have this call :

// some code;
myAjaxCall(
      function abcd() {};
);

// more code

Can the more code and abcd executing in the same thread or different thread. I know it is asynchronous.

possible duplicate of http://stackoverflow.com/questions/1510011/how-does-ajax-work — bensiu, Mar 16 '11 at 22:19

Josiah Ruddell · Accepted Answer · 2011-03-16T22:19:21.037

3

Assuming myAjaxCall is an ajax wrapper, and the first argument is the complete callback, the answer is "more code" will run before abcd function. But I'd need to see myAjaxCall function to know what is really going on.

Remember, the complete callback happens when ajax retruns. "more code" executes in the normal execution path.

edited Mar 16 '11 at 22:19

answered Mar 16 '11 at 22:14

Josiah Ruddell

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Why does it matter what is in `myAjaxCall`? – javaguy Mar 16 '11 at 22:20
because I don't know how that first argument is used. If, inside `myAjaxCall` arruments[0] is called, it would happen first. – Josiah Ruddell Mar 16 '11 at 22:21

score 2 · Answer 2 · answered Mar 16 '11 at 22:20

The AJAX request is asynchronous, but the Javascript code is synchronous and single threaded.

The code following the AJAX call will complete before the abcd function can run. The event that occurs when the response arrives can't be handled until the code exits and returns control to the browser.

How Does AJAX work

2 Answers2

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