知道何时阵列的jqXHR全部完成

Question

I'm trying to run some code once all the jqXHR elements of an array are completed (have either succeeded or failed).

You can see the full code here: http://jsfiddle.net/Lkjcrdtz/4/

Basically I'm expecting the always hook from here:

$.when
    .apply(undefined, reqs)
    .always(function(data) {
      console.log('ALL ALWAYS', data);
    });

to run when all the requests that were piled up there have either succeeded or failed. Currently, you can observe in the console that ALL ALWAYS is logged earlier.

Answer 1

A simple solution for modern browsers would be to use the newer fetch() API along with Promise.all()

 var makeReq = function(url, pos) { var finalUrl = url + pos; // intentionally make this request a failed one if (pos % 2 === 0) { finalUrl = "https://jsonplaceholder.typicode.com/423423rfvzdsv"; } return fetch(finalUrl).then(function(resp) { console.log('Request for user #', pos); // if successful request return data promise otherwise return something // that can be used to filter out in final results return resp.ok ? resp.json() : {error: true, status: resp.status, id: pos } }) }; // mock API var theUrl = "https://jsonplaceholder.typicode.com/users/"; var reqs = []; for (var i = 1; i <= 5; i++) { reqs.push(makeReq(theUrl, i)); } Promise.all(reqs).then(function(results) { console.log('---- ALL DONE ----') // filter out good requests results.forEach(function(o) { if (o.error) { console.log(`No results for user #${o.id}`); } else { console.log(`User #${o.id} name = ${o.name}`); } }) })