js promise

JQuery 3.0 Alpha released, Deferred compatible with Promise JQuery 3.0 preview version is released. This version is the first Alpha preview version of jQuery 3.0! Major features of this version: Support for modern browsers and IE9 environments. Also released the jQuery Compat 3.0 Alpha version, which has the following features: Support for IE8! Both jQuery 3.0 Alpha and jQuery Compat 3.0 Alpha support Yandex. A browser released in 2012 can be downlo

Promise objects in the ES6var p = new Promise (function (resolve, reject) { window.settimeout (function () { Console.log ("1", 1); Resolve (1); },10);}); P.then (function (a) { return new Promise (function (resolve,reject) { window.settimeout (function () { Console.log ("2", a+1); Resolve (A + 1); },10);}

This was a solution to the situation where you had an asynchronous task of want to perform over and over again, in a non- Blocking fashion, stopping when some condition was met.To set the stage, I'll be using the Bluebird Promise Library, the best Promise library I ' ve used.First, we ll construct the Promise function which would do the looping:varPromise = requi

/** * Created by liyinghao on 2016/11/6. */ const fs = require(‘fs‘); /* * 新建一个Promise对象,Promise就是一个容器,里面放置一个异步执行的API * */ const p1 = new Promise((resolve, reject)=>{ fs.readFile(‘./a.txt‘,‘utf8‘,(err,data)=>{ if(err){ /* * 容器中异步任务失败之后调用reject方法,把错误对象传递给reject,同时终止程序的执行 * */ return reject

/** * Created by liyinghao on 2016/11/6. */ const fs = require(‘fs‘); /* * 新建一个Promise对象,Promise就是一个容器,里面放置一个异步执行的API * */ const p1 = new Promise((resolve, reject)=>{ fs.readFile(‘./a.txt‘,‘utf8‘,(err,data)=>{ if(err){ /* * 容器中异步任务失败之后调用reject方法,把错误对象传递给reject,同时终止程序的执行 * */ return reject

Written in front: as an entry-level rookie, when the project cut the environment with NODE,VUE,ES6, found to learn to understand the things there are too many, before even promise is a nothing to know.Turned over the book said promise is abstract asynchronous processing of objects and its various operations of the component, a little abstraction to understand is not AH ~ So consulted the great GodSimply put

Promise and Async/await are asynchronous schemes, promise is a new feature of ES6, and Async/await is a new feature of ES7. And for Async/await is based on promise, he can let us more elegant writing code, and instead of the then (), such as:Const F = () = { returnnew Promise ((resolve, reject) = { = = { rejec

Angular.module (' myApp ', []). Controller (' Dashboardcontroller ', [ ' $scope ', ' githubservice ', function ($ Scope, Githubservice) { githubservice.getpullrequests () . Then (function (data) { $scope. pullrequests = (data; });}]). Factory (' Githubservice ', [ ' $q ', ' $http ', function ($q, $http) { var getpullrequests = function () { var deferred = $q. Defer (); Get list of open angular JS pull r

Use Promise to solve code nesting problems caused by multiple asynchronous Ajax requests (perfect solution), promiseajax Problem When the front-end students made pages, they made a common mistake: they wrote down multiple Ajax requests in sequence, while the subsequent requests returned results for the previous requests, yes. The following code is used: Var someData; $. ajax ({url: '/prefix/entity1/action1', type: 'get', async: true, contentType: "app

Project needs, see a bit of Nodejs, which is more difficult to understand is promise, record a learning Bluebird provide promise implementation.Promise.promisifyall (obj) methodFunction: The object's Method property becomes an async method, and the suffix async is appended to the function.Look at the following code:var Promise = require (' Bluebird ')var obj = {

Follow the previous "One Promise Practice: Asynchronous Task grouping scheduling", this time is also from the work of the actual problems encountered.This encounter problem can be likened to a batch of raw materials processing, wherein the beginning of some of the process is the same, like the assembly line, the beginning of a paragraph is the same, the back is divided into two streams, on this basis, respectively, the production of different products

The purpose of promise is to jump out of the back of Hell. Old thing, big God Pat.For the simplest example: request data (GetData), parse data (executedata), display data (ShowData). //Get Data functionGetData (callback) {callbackcallback (); } //parsing Data functionExecutedata (callback) {callbackcallback (); } //Show Data functionShowData (callback) {callbackcallback (); } //started requesting data.G

Reference http://www.ruanyifeng.com/blog/2011/08/a_detailed_explanation_of_jquery_deferred_object.htmlThe Ajax method has been rewritten since the jQuery1.5 version, not the same as it used to be. Now $.ajax () will return a Promise/deffered objectThis object has the Do () fail () always () and then () Promise () reject () methodsI used to write Ajax like this,$.ajax ({URL: "Test.html",Success:function () {

about what is promise and promise solve the problem, please experience node callback asynchronous coding Dafa, incidentally Http://wiki.commonjs.org/wiki/Promises/A to see how it is defined, no longer repeat. Here we look at how to implement the node API promise with Q.js. First, everything is install Copy Code code as follows: NPM Install Q

Always enjoy using native JavaScript, especially if you don't need to consider compatibility scenarios (albeit pitifully). Unfortunately ECMAScript does not encapsulate a good Ajax method (in fact, there is no need to have), the use of their own promise a bar. Get function Getjson (URL) {return new Promise (Resolve, Reject) => { var xhr = new XMLHttpRequest () Xhr.open (' Get ', url, tr

HTTP://WWW.CNBLOGS.COM/HAIPPY/P/3279565.HTMLSTD: Introduction to the class of the:p romiseThe Promise object can hold the value of a type T, which can be read by the future object (possibly in another thread), so promise also provides a means of thread synchronization. Promise object constructs can be associated with a shared state (typically Std::future) and a v