deferred

问题 I need to make a series of N ajax requests without locking the browser, and want to use the jquery deferred object to accomplish this. Here is a simplified example with three requests, but my program may need to queue up over 100 (note that this is not the exact use case, the actual code does need to ensure the success of step (N-1) before executing the next step): $(document).ready(function(){ var deferred = $.Deferred(); var countries = [\"US\", \"CA\", \"MX\"]; $.each(countries, function

问题 The $q service is very powerful in angularjs and make our life easier with asynchronous code. I am new to angular but using deferred API is not very new to me. I must say that I completely ok with the How to use part of documentation + there are very useful links for that within the docs + I checked out the source either. My question is more about the under the hood parts of deferred and promise API objects in angular. What are the exact phases in their life cycles and how are they interacts

问题 I want to have a for-loop which calls async functions each iteration. After the for-loop I want to execute another code block, but not before all the previous calls in the for-loop have been resolved. My problem at the moment is, that either the code-block after the for-loop is executed before all async calls have finished OR it is not executed at all. The code part with the FOR-loop and the code block after it (for complete code, please see fiddle): [..] function outerFunction($q, $scope) {

问题 Problem 1: only one API request is allowed at a given time, so the real network requests are queued while there\'s one that has not been completed yet. An app can call the API level anytime and expecting a promise in return. When the API call is queued, the promise for the network request would be created at some point in the future - what to return to the app? That\'s how it can be solved with a deferred \"proxy\" promise: var queue = []; function callAPI (params) { if (API_available) { API

问题 I have three HTTP calls that need I need to make in a synchronous manner and how do I pass data from one call to the other? function first() { ajax() } function second() { ajax() } function third() { ajax() } function main() { first().then(second).then(third) } I tried to use the deferred for the two functions and I came up with a partial solution. Can I extend it to be for three functions? function first() { var deferred = $.Deferred(); $.ajax({ \"success\": function (resp) { deferred

问题 What are the differences between Deferreds, Promises and Futures? Is there a generally approved theory behind all these three? 回答1: In light of apparent dislike for how I've attempted to answer the OP's question. The literal answer is, a promise is something shared w/ other objects, while a deferred should be kept private. Primarily, a deferred (which generally extends Promise) can resolve itself, while a promise might not be able to do so. If you're interested in the minutiae, then examine

问题 I am have a problem understanding why rejections are not passed on through a promise chain and I am hoping someone will be able to help me understand why. To me, attaching functionality to a chain of promises implies an intent that I am depending on an original promise to be fulfilled. It\'s hard to explain, so let me show a code example of my problem first. (Note: this example is using Node and the deferred node module. I tested this with Dojo 1.8.3 and had the same results) var d = require(