asynchronous javascript example

It is like waiting in the queue. The people in front of the queue are busy and suddenly go to the toilet. the people behind the queue are blocked here. Therefore, we need to let the people in front of the queue die and let the people behind follow up ...... AJAX is the concept. The request continues, but we can do other things.The setTimeout Function of BOM is implemented in javascript, but DOM operations also provide a series of implementations. For

. Copy Code code as follows: Callbackresult = callback (Self.result); Self.result = Callbackresult; if (callbackresult callbackresult instanceof async.operation) { Innerchain = Async.chain (); while (Callbackqueue.length > 0) { Innerchain.next (Callbackqueue.shift ()); } Innerchain.next (function (result) { Self.result = result; Self.state = "Completed"; Self.completed = true; return result; }); Callbackresult.addcallback (function (result) { Self.res

); } }, 1); return this; } By using settimeout, we ensure that the actual operation of the yield is done asynchronously. We then update the results of the user's incoming yield and the related state to the object properties, and then traverse Callbackqueue to invoke all the callback functions. Summary So we do a simple JavaScript asynchronous invocation framework, the complete code can loo

update the user-passed yield results and related statuses to the object attributes, and finally traverse callbackQueue to call all the callback functions.Summary In this way, we have completed a simple JavaScript asynchronous call framework. The complete code can be viewed here: asynchronous call framework Async. Operation.This framework can well solve the coexi

user-passed yield results and related statuses to the object attributes, and finally traverse callbackQueue to call all the callback functions.Summary In this way, we have completed a simple JavaScript asynchronous call framework. The complete code can be viewed here: asynchronous call framework Async. Operation.This framework can well solve the coexistence of s

var start = new Date; SetTimeout (function () { var end = new Date; console.log (' end~~~ ', End-start, ' Ms '); },0); while (new Date-start if (new Date-start = = 3999) console.log (' End ') } Start timing after running settimeout, and put the callback function at the end of the delay event queue. After all the synchronous JS events are completed, the settimeout callback function is executed, even if the SetTimeout setting event is less than the event run by the synchronization event, the

methods events. Events Node.js all asynchronous I/O operations will send an event to the event queue when they are completed. Many objects in Node.js distribute events: A Net.server object distributes an event each time a new connection is made, and a Fs.readstream object emits an event when the file is opened. All of the objects that generate the event are events. An instance of Eventemitter. Eventemitter class The events module provides only one ob

The interaction of Web pages is becoming more and more complex, and the asynchronous operation of JavaScript is more and more. such as the common Ajax request, need to respond when the request completes, the request is usually asynchronous, the request in the process of the user can do other operations, will not block the page, this

Asynchronous upload of Images Using Ajax (html, javascript, php) and ajaxjavascript Two days ago, the project needed to use the asynchronous upload of images and display of the upload progress function. So I found many foreign articles and ran into various pitfalls. Here I wrote an article to record them.HTML There is nothing to say about HTML code. There is a

Understanding jquery before implementing an asynchronous queue, it is necessary to understand the JavaScript asynchronous Pattern. JavaScript Async is not really a serious sense of asynchrony, JS makes certain fragments asynchronous way in the future, the stream does not hav

Link: http://hi.baidu.com/tommickey/blog/item/4270a1580eaccf82810a186e.html Ajax is called "Asynchronous JavaScript and XML" (Asynchronous JavaScript and XML). It is a Web page development technology used to create interactive web applications. It mainly includes the following technologies Ajax (

specific implementation of the function. For this reason, we will write another example:Copy codeThe Code is as follows:Async. go (0). Next (function (I) {alert (I); return I + 1 ;}). Next (function (I ){Alert (I );Var operation = new Async. Operation ();SetTimeout (function () {operation. yield (I + 1) ;}, 1000 );Return operation;}). Next (function (I) {alert (I); return I + 1 ;}). Next (function (I) {alert (I); return I ;}); In the above example, w

The following code, how long will the ' end ' pop up? Why? The code is as follows Copy Code var t = true;settimeout (function () {t = false;}, 1000);while (t) {}Alert (' End '); This is an implementation that was previously thought of when you could not implement a blocking JavaScript thread (that is, to implement the Sleep method).It's simple, isn't it?Is it? Re-recognize