JQuery - $.when syntax for array of Deferred objects
deferred, jquery, syntax
Solution
Yes, I have stumbled upon this as well: `when` does not easily allow to be passed an array. But you could use `apply` to achieve the desired result.
$.when.apply($, getCustomerDataCalls(customerIds))
Problem
It is the first time I am using `$.when` and I am having difficulty with the syntax. I have code similar to simplified example below. It works (if I haven't caused an error when I simplified it). My problem is that I don't know home many elements the `customerIds` array would contain. ``` var customerIds = new [1, 2, 3]; $.when( getCustomerData(customerIds[0]), getCustomerData(customerIds[1]), getCustomerData(customerIds[2]) ).then(function() { alert('success'); }).fail(function() { alert('error'); }); function getCustomerData(int id) { return new $.Deferred(function(defer) { doSomeWork(id, defer); }).promise(); } ``` I would like to write the `$.when` statement as follows but having difficulty getting the syntax right. ``` $.when( getCustomerDataCalls(customerIds), ).then(function() { alert('success'); }).fail(function() { alert('error'); }); ``` Where `getCustomerDataCalls` is implemented as: ``` function getCustomerDataCalls(customerIds) { var dfds = []; for (var id in customerIds) { dfds.push(new $.Deferred(function(defer) { doSomeWork(id, defer); }).promise()); } return dfds; } ``` Unfortunately something is wrong with my implementation and I cannot work out where I am going wrong. My best guess is that something is going wrong when returning an array of `Deferred`s Update: I updated the code after lanzz mentioned that my contrived example already returns a Deferred, I updated my example to include `doSomeWork`