I am no beginner in javascript. I am actually working on this for past 3-4 months but today I read this statement about "What is JavaScript?" JavaScript is single-threaded, non-blocking, asynchronous, concurrent language. and I was lost. If JavaScript is single-threaded, how can it be concurrent and how can it be asynchronous because you need to keep track what your async code is
我不是JavaScript的初学者。 实际上，我正在为此工作3-4个月，但今天我阅读了关于“什么是JavaScript？”的声明。 JavaScript是单线程的，非阻塞的，异步的并发语言。 我迷路了。 如果JavaScript是单线程的，它怎么可能是并发的？它怎么可能是异步的，因为你需要跟踪你的异步代码正在做什么，而没有另一个线程，不可能同时跟踪2个或更多的代码？ 啊..这是事情： JavaScript是单线程的，但它有很多空闲时间。 当它正在
The event-driven programming model of node.js makes it somewhat tricky to coordinate the program flow. Simple sequential execution gets turned into nested callbacks, which is easy enough (though a bit convoluted to write down). But how about parallel execution? Say you have three tasks A,B,C that can run in parallel and when they are done, you want to send their results to task D. With a f
node.js的事件驱动编程模型使协调程序流程有点棘手。 简单的顺序执行变成了嵌套的回调，这很容易（尽管有点复杂的写下来）。 但是并行执行怎么样？ 假设你有三个任务A，B，C可以并行运行，当他们完成后，你想把他们的结果发送给任务D. 用叉/连接模型，这将是 叉A 叉B 叉C 加入A，B，C，运行D 我如何在node.js中编写它？ 有没有最佳做法或食谱？ 我是否每次都必须手动推出解决方案，或者是否有一些图书馆有助
I want to make a page that displays some data from a DB, so I have created some functions that get that data from my DB. I'm just a newbie in Node.js, so as far as I understand, if I want to use all of them in a single page (HTTP response) I'd have to nest them all: http.createServer(function (req, res) { res.writeHead(200, {'Content-Type': 'text/html'}); var html = "<h1>Demo
我想创建一个页面来显示数据库中的一些数据，所以我创建了一些从我的数据库中获取数据的函数。 我只是Node.js中的一个新手，据我所知，如果我想在单个页面中使用它们（HTTP响应），我必须将它们全部嵌套在一起： http.createServer(function (req, res) { res.writeHead(200, {'Content-Type': 'text/html'}); var html = "<h1>Demo page</h1>"; getSomeDate(client, function(someData) { html += "<
I'm trying to pluck some key-values from json array and form another array, below is the sample json structure. I got one solution now. Just want to know what are the other methods to do the same. Is there anyway to reject keys from array of objects. Input var a = [{ id: 1, name: "First Name", description: "" },{ id: 2, name: "Second Name", description: "" }] Outp
我试图从json数组中取出一些键值并形成另一个数组，下面是示例json结构。 我现在有了一个解决方案。 只是想知道有什么其他的方法来做同样的事情。 无论如何拒绝从对象数组中的键。 输入 var a = [{ id: 1, name: "First Name", description: "" },{ id: 2, name: "Second Name", description: "" }] 产量 [{ id: 1, name: "First Name" },{ id: 2, name: "Second Name" }] 一个解
I'd like to cycle through an array of words creating a text rotation affect. I have most of it working as expected. Is there any way I can use a css transition on the length of the p element? When traversing from an object with char.length > 10 to an object with char.length < 5 (for example) the movement isn't smooth and I'd like to ease the movement of the text around the w
我想循环查看一组创建文字旋转效果的单词。 我大部分工作如预期。 有什么办法可以在p元素的长度上使用css转换吗？ 当从char.length> 10的对象遍历到char.length <5的对象时（例如），运动不平滑，我想缓解文本在单词周围的移动，而不是突然向后跳跃（或转发取决于单词的长度） HTML： <p><span id="description-rotate"></span> something built on something else.</p> 上海社会科学院：
Javascript 1.9.3 / ECMAScript 5 introduces Object.create , which Douglas Crockford amongst others has been advocating for a long time. How do I replace new in the code below with Object.create ? var UserA = function(nameParam) { this.id = MY_GLOBAL.nextId(); this.name = nameParam; } UserA.prototype.sayHello = function() { console.log('Hello '+ this.name); } var bob = new UserA('bob'
JavaScript 1.9.3 / ECMAScript 5引入了Object.create ，道格拉斯克罗克福德等人长期以来一直主张。 如何用Object.create在下面的代码中替换new的？ var UserA = function(nameParam) { this.id = MY_GLOBAL.nextId(); this.name = nameParam; } UserA.prototype.sayHello = function() { console.log('Hello '+ this.name); } var bob = new UserA('bob'); bob.sayHello(); （假设存在MY_GLOBAL.nextId）。 我
Im' having problems with JQuery and Internet Explore (IE). My method for adding rows doesn't seem to be working in IE (Chrome & Firefox pose no problem) Imagine following table <table border="1"> <tr> <td><button class="btn">btn1a</button></td> <td><button class="btn">btn1b</button></td> <td
我'有问题与JQuery和Internet Explore（IE）。 我的方法添加行似乎并没有在IE浏览器中工作（铬和Firefox构成没有问题） 想象下面的表格 <table border="1"> <tr> <td><button class="btn">btn1a</button></td> <td><button class="btn">btn1b</button></td> <td>zever</td> <td>zeverin pakskes<
I'm developing a HTML5 game and I need to know if updating localStorage properties frequently can slow down the page. I'm actually storing my hero's position in four localStorage properties (two for the actual position and two for the past position to use in a collision detection system) and updating it every 1 second interval, but I want to update it at 60fps to save every hero mov
我正在开发一个HTML5游戏，我需要知道是否经常更新localStorage属性会降低页面的速度。 实际上，我将英雄的位置存储在四个localStorage属性中（两个用于实际位置，两个用于碰撞检测系统中的过去位置）并每隔1秒更新一次， 但我希望以60fps更新以保存每一个英雄运动。 在该频率使用localStorage会导致性能问题？ 本地存储将数据存储在用户硬盘上。 读取和写入硬盘需要比RAM更长的时间。 结论是，您可以通过在启动时从本
I have a (generated) page with a very large jagged array. It does not initialize in IE11; I get SCRIPT28: Out of stack space and SCRIPT2343: Stack overflow at line: 1 . I have reduced the problematic page to the bare minimum with randomized data, and this is what it looks like: <html><body> <div id="info"> Loading... </div> <script> v
我有一个非常大的锯齿状数组的页面（生成）。 它不会在IE11中初始化; 我得到SCRIPT28: Out of stack space SCRIPT2343: Stack overflow at line: 1 。 我用随机数据将有问题的页面减少到了最低限度，这就是它的样子： <html><body> <div id="info"> Loading... </div> <script> var d = []; var i = 0; d[i++] = [ "XHC_14", 0
As of jQuery 1.9 the .selector property of jQuery objects has been removed. (I'm a little confused as to why, exactly). I actually use it in a few unique scenarios, and I know that I could do other things to prevent this. Just wondering if anyone knows another way of grabbing the selector as of 1.9? $('#whatever').selector // (would of returned '#whatever') One example of where I need
从jQuery 1.9开始，jQuery对象的.selector属性已被删除。 （我有点困惑，为什么，确切地说）。 我实际上在一些独特的场景中使用它，并且我知道我可以做其他事情来防止这种情况发生。 想知道是否有人知道另一种抓取选择器的方式？ $('#whatever').selector // (would of returned '#whatever') 我需要.selector的一个示例是，当我已经有一组名称为复选框时，我想在该组内检查选中哪一个： jsFiddle DEMO var $test = $('