How to make code wait while calling asynchronous calls like Ajax

Question

I am looking for something like this  function someFunc      callAjaxfunc      may have multiple ajax calls in this function someWait       some code which waits until async calls complete console log  Pass2        function callAjaxfunc         All ajax calls called here   console log  Pass1         What I have tried   1     Jquery when    tried using it  it works fine  But not the way I want    when will wait but the code next to   when   runs with out waiting  The code inside do callback only runs after ajax calls  2  setTimeOut   with a global flag  I was so confident this will work  I tried like following   GlobalFlag   false   function someFunc            callAjaxfunc      may have multiple ajax calls in this function     setTimeOut waitFunc  100      some  which waits until async calls complete     console log  Pass2       function callAjaxfunc           All ajax calls called here     onAjaxSuccess  function             GlobalFlag   true             console log  Pass1           function waitFunc         if   GlobalFlag            setTimeOut waitFunc  100              Still not able to get wanted result  Am I doing something wrong here  This is not the way   Result I wanted should come like this  Pass1 Pass2   Not able to make any fiddle as it needs AJAX calls  EDIT  As many were suggesting callbacks  i know about them  but still the code next to somewait   will get executed   I want browser to completely stop executing code next to somewait   until the ajax call  Also it may be a bad practice but worth to know and try if possible

User · Answer

If you need wait until the ajax call is completed all do you need is make your call synchronously

User · Answer

Why didn t it work for you using Deferred Objects  Unless I misunderstood something this may work for you      AJAX success handler    var echo   function         console log  Pass1        var pass   function         when         AJAX requests          post   echo json      delay  1    echo         post   echo json      delay  2    echo         post   echo json      delay  3    echo      then function            Run after all AJAX        console log  Pass2                See it here     UPDATE  Based on your input it seems what your quickest alternative is to use synchronous requests  You can set the property async to false in your   ajax requests to make them blocking  This will hang your browser until the request is finished though   Notice I don t recommend this and I still consider you should fix your code in an event-based workflow to not depend on it

User · Answer

Real programmers do it with semaphores   Have a variable set to 0  Increment it before each AJAX call  Decrement it in each success handler  and test for 0  If it is  you re done

User · Answer

Use callbacks  Something like this should work based on your sample code   function someFunc      callAjaxfunc function         console log  Pass2            function callAjaxfunc callback          All ajax calls called here     onAjaxSuccess  function             callback               console log  Pass1            This will print Pass1 immediately  assuming ajax request takes atleast a few microseconds   then print Pass2 when the onAjaxSuccess is executed

[javascript] How to make code wait while calling asynchronous calls like Ajax

Examples related to javascript

Examples related to jquery