ecmascript-5

问题 The following function does an amazing job of retrieving a deep object key value with a dot notated string: function getPathValue(obj, path) { return new Function('_', 'return _.' + path)(obj); } For example, it returns the value for a key like "bar" using the following as the path argument: 'data.abc.foo.bar' However, some API's pack additional stringified JSON into some key values. I'm looking for an enhancement to the above function that will handle that case. For example, Stack's own

问题 Core Question I need help coming up with a concept to achieve my goal. I am having a problem coming up with an idea to how I can navigate the DOM properly with the method I have chosen. The Goal You should know what I am doing first: I use ajax to call HTML content into a <section> element of my template. I then call from those HTML contents an class="pageNav" tagged element that holds the sub navigation for it and copies it to a id="subNav" located in the main template. I do this when the

问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: Javascript null or undefined null is a reserved word but not a keyword. Hence it can not be over-written. undefined is a built in global that can be over-written. This is why you see jQuery re-define it in its IIFE. Just to make sure it was not over-written. What it the technical distinction of when to use each as specified in ES 5. I know that I have seen browsers set an un-created localStorage property to

问题 I'm trying to implement some basic operations to the Set object like says here This is the code export class Conjunto extends Set<any>{ constructor(initialValues?) { super(); return new Conjunto(initialValues); } isSuperset(subset) { //some code } } Do you guys have any idea to make it work? or am I doing something wrong? For the moment I'm using the hack this guy found here 回答1: if you are trying to add functions to the Set prototype, or add polyfills to Set, you can do the following:

问题 I am fearful of "scope soup", people hanging too much functionality off the $scope. So I am experimenting with OO oriented controllers, the new controllerAs and using EC5 style getter / setters in my controller. That is working sweet, but now I want to bind my directive's scope to my controller's scope two way, and it isn't working as I expect. I have created this codePen to show it. http://codepen.io/anon/pen/DlfxB?editors=101 I expect this line to work: scope: { pants: '='}, 回答1: You can

问题 I think it is an old Javascript behavior (Crockford said it is a design error) that inside a function, arguments is like an array, except it is not a real array, so array methods cannot be invoked on it: function foo() { console.log(arguments.slice(1)) } // won't work foo(1,2,3); And I just tried it on the latest Firefox and Chrome, and it won't work on both. So we may have to use function foo() { console.log(Array.prototype.slice.call(arguments, 1)) } foo(1,2,3); But why not make arguments a

问题 In JavaScript functions, arguments is an array-like object containing all arguments to the function, whether they are named or not: function f(foo, bar) { console.log(arguments); } f(1, '2', 'foo'); // [1, "2", "foo"] Is there a way to get only the arguments that are not named, so you could do something like this? function f(foo, bar) { console.log('foo:', foo, 'bar:', bar, 'the rest:', unnamedArguments); } f(1, '2', 'foo'); // foo: 1 bar: "2" the rest: ["foo"] But why? A real-world use case

问题 We are using wro4j with Google Closure and Maven to minify our JS. By default it does not suport strict mode in the JS ("use strict";).. it just strips it out. Is there any configuration I can do in pom.xml or somewhere else to get it to leave use strict in there? This is the configuration for google closure complier to do it: --language_in=ECMASCRIPT5_STRICT Not sure how to plug that in to Wro4j. Any ideas? 回答1: Create a custom implementation of the manager factory which adds ECMAScript5:

问题 This question already has answers here : Javascript - sort array based on another array (18 answers) Closed 2 years ago . Is it possible, rather easily, to sort an array of objects by an array of IDs? Here's an example: [{ id: "A", name: "John" }, { id: "B", name: "Bobby" }, { id: "C", name: "Peter" }] Now I have an array of objects, each with an unique ID. I then have an array of IDs like so: var ids = ["C", "A", "B"]; Would it be possible to sort the array of objects, so it ends up like

问题 Recently I've started to learn ReactJS and consequently - ES6. I'm quite familiar with ES5, but some things are not that clear for me. Example 1: Methods syntax What is the difference between the following two methods? export class InvoiceForm extends React.Component { methodName1() { } methodName2 = () => { }; } Example 2: Class properties outside class Greeting extends React.Component { render() { return ( <h1>Hello, {this.props.name}</h1> ); } } Greeting.propTypes = { name: PropTypes