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zlati.peh..

about when-then

in Using jQuery • 11 years ago

Hi,

Recently I saw the

$.when().then(function(){ })

functionality.

The examples are talking about usage in case i need to wait for a successive ajax request, and use it's deferred in "then". I would like to use that functionality to execute to different each loops, obligatory one after another.

$.when(
$(element).each(function(i,obj){
// something here
})
).then(function(){
$(element2).each(function(i,obj){
// something other here
});
})

The question appears because I don't know if "each" is returning deferred

and can "when" understand if the loop has finished

Replies(9)

kbwood.au

Re: about when-then

11 years ago

You don't need when/then here, unless you are doing something asynchronously within the first each. Normally the first each must finish before the second is run.

zlati.peh..

Re: about when-then

11 years ago

What happens if in place of // something here

I put call of function that does ajax call with async:true, (will it work with async:false?)

Kevin B

Re: about when-then

11 years ago

in that case you need to pass the promise objects into the .when(), .map with .apply makes this easy.

$.when.apply("",$.map(function(){
return $.ajax({...});
}).get()).then(function(){
// do something else
});

-- Kevin

zlati.peh..

Re: about when-then

11 years ago

strange behavior when $.when is containing only one parameter

in done ajax has returned a responseText

http://jsfiddle.net/E4mz9/25/

Kevin B

Re: about when-then

11 years ago

The way i understand it is if only one object is passed in, the results of it are passed as the only parameter to done. If multiple objects are passed in, the result of each one is returned as a parameter to the $.when.

$.when( deferredObject1, deferredObject2, deferredObject3 ).done( function (resultsOne, resultsTwo, resultsThree) {

console.log(arguments);

});

If there is only one deferred object, it acts as-if you simply used deferredObject.done()

-- Kevin

zlati.peh..