使用Ajax并行页面加载

Question

Suppose I have a page which contains a four blocks. Each block contains a lot of html code. It take a lot of time to load whole page especially in old browsers like ie8. Could I speed up page loading using ajax requests? I mean send ajax request to get each part of the page. Someone tell me that ajax requests working in parallel instead of single thread page render that's why it will help to decrise page loading time. Is it true?

Answer 1

All I/O operations on javascript runs in parallel, you only need to start all of them and wait for all to complete, promises (aka Deferreds on jQuery) was designed for that using .when . Example:

$.when(
  $.get("/resource1"),
  $.get("/resource2"),
  $.get("/resource3")
).done(function(response1, response2, response3) {
  // do things with response1, response2 and response3;
});

more info: http://learn.jquery.com/code-organization/deferreds/jquery-deferreds/