jQuery Deferred - waiting for multiple AJAX requests to finish -

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• pass in array of deferreds $.when() 9 answers

i have 3 layer deep chain of deferred ajax calls, , ideally going kick promise way when deepest layer finishes (makes me thing of inception... "we need go deeper!").

the problem i'm sending off many ajax requests (possibly hundreds) @ once , need defer until of them done. can't rely on last 1 being done last.

function updateallnotes() {     return $.deferred(function(dfd_uan) {         getcount = 0;         getreturn = 0;         (i = 0; <= index.data.length - 1; i++) {             getcount++;             $.when(getnote(index.data[i].key)).done(function() {                 // getnote deferred                 getreturn++             });         };         // need here         // when getreturn == getcount, dfd_uan.resolve()     }).promise(); }; 

you can use .when(), , .apply() multiple deferred. extremely useful:

function updateallnotes() {     var getarray = [],         i, len;      (i = 0, len = data.length; < len; += 1) {         getarray.push(getnote(data[i].key));     };      $.when.apply($, getarray).done(function() {         // things need wait until gets done     }); }