es6 for beginners

the destructor assignment of a variable: ES6 allows you to extract values from arrays and objects in a certain pattern, assigning values to variables, which is called deconstruction (destructuring). The previous wording:var a = 1;var B = 2;ES6 allowable wording:Let [A, b] = [+];General Purpose:1. Value of exchange variable[x, Y] = [y,x];2. function returns multiple valuesFunction F1 () {return [+];} var [a,

1.array.from ()(1) converting to an arrayThe ①array.from () method canclass Array Object (The so-called array-like object, the intrinsic feature is only one point, that is, the length property must be. Therefore, any object with the Length property can be converted to an array by means of the Array.from method , at which point the extension operator cannot be converted. )and Ergodic (iterable) objects into real arrays. Includes ES6 new data structure

1. Let commandTips: Block-level scope (valid only in the current block) No variable promotion (must first be declared in use) Let the variable monopolize the block, no longer subject to external influence Duplicate declarations are not allowed In short: Let's more like the variable declaration directives of the static language we know wellES6 has a new let command to declare variables. The usage is similar to Var, but the declared variable is valid only within the code

ES6 today officially released (Roadside News), anyway, it will be released this month, before a lot of ES6 features have been fired very hot, but the total feeling and we have little relationship, because either some have not supported, or practicality is not very large, But today is a method that you must be familiar with or have used or heard.Believe that engaged in the front-end must have used angular ba

A simple example of using babel to convert es6 syntax to es5, babeles6 syntax es5 Preface Babel is a widely used Transcoder that can convert ES6 code into ES5 code for execution in an existing environment. This means that you can write programs in ES6 now without worrying about the support of the existing environment. This article describes how to pre-insta

ES6 provides MAP, it is a set of k-v pair. Key can be number, string, object, function and even undefined.var New Map ();Methods: 1. Set (K,V)M.set ("edition", 6) // key is the string m.set (262, "standard") // key is numeric M.set ( Undefined, "nah") // key is undefinedvarfunction() {console.log ("Hello" // key is a function2. Get (k)M.get (Hello) // Hello es6! M.get ("edition")

Preface: After so long, small rookie finally began to formally apply react, and ES6 to develop the project. Before like a classmate of a blog style, here to paste the address: Https://iwenku.net/,PC End is what he did long ago, he recently re-made a move. After reading, I also sketched out a blog, so I began to formally build their own blog as a project practiced hand bar. First, build the environment1, install nodeThe first step is to make sure

Array.from ()Array.fromThe Array-like method is used to convert two types of objects to a true array: An array-like object (A. iterable) and an object that can be traversed (including ES6 new data structure set and map).1Let Arraylike = {2' 0 ': ' A ',3' 1 ': ' B ',4' 2 ': ' C ',5Length:36 };7 8 //the writing of ES59 varARR1 = [].slice.call (arraylike);//[' A ', ' B ', ' C ']Ten One //the writing of ES6 AL

Today Vue Project NPM Run build after Webpack, error UGLIFYJS, their own research, translated, meaning is not recognized in the project to write advanced grammar, here to the project ES6 syntax es5 let the browser recognize,That is Webpack's Babel need to be configured underBabel is actually a platform for compiling JavaScript, and its strength is that it can be compiled to help you achieve the following: Use the next generation of JavaScript co

Commonjs and AMD essentially define a namespace with a global variableTake Sea.js as an example, each module outputs an object, and the object is mounted under the Seajs.cache property, and each module exists as an object.While the ES6 module is not, the module object does not exist when the module is not referenced.Commonjs and AMD are run-time loaded, ES6 modules are loaded at compile timeThis distinction

The first thing to say is the array: the array is classified as object, which is a special object, and the index value of the array is similar to the object's key value.Several points of note for arrays :1. The length of the array is a readable property and cannot be changed, and the length of the array is based on the index maximum value.2. The index value of an array can be a string, etc., but this does not affect the length of the array.3. The array is automatically filled with the correspond

A few new ways to ES6 arrays:1. ForEach ()// ForEach () iterates through an array with no return value and does not change the original array var arr=[1,2,3,4]arr.foreach ((item,index,arr)={ console.log (item); // 1,2,3,4})2. Map ()// map () iterates through an array, returns a new array, and does not change the value of the original array var arr=[1,2,3,4]arr.map ((item,index,arr)={ return item*10; // returns the new array 10,20,30,40})3

, Date.now3.Object method Object.getprototypeofObject.createObject.getownpropertynamesObject.definepropertyObject.getownpropertydescriptorObject.definepropertiesObject.keysObject.preventextensions/object.isextensibleObject.seal/object.issealedObject.freeze/object.isfrozenPS: There is nothing to say but what to say. What is ES6ECMASCRIPT6 provides a number of new features in the context of guaranteed backwards compatibility, and is currently compatible with the following browsers:Th

ES6 provides us with two data structures set and map, which are sometimes convenient for us to process our data. The two methods are analyzed directly. One, set data structure Set itself is a constructor that is used to generate set data structures, similar to arrays, but whose values are unique.The set internally determines whether two values are different, similar to the exact equality operator (= = =), the main difference being that nan equals itse

IntroductionThe current react front-end frame is the hottest this year. React native, based on react, also developed rapidly. React has its unique component function and jsx new syntax to help the front-end design with better design and convenience, and react native is to expand the front-end boundaries.Speaking of react, you have to say that Webpack, with its excellent features such as asynchronous loading and detachable packaging, is on the way to replace grunt and gulp. And the future-oriente

This article describes how to parse the deconstruct assignment in the JavaScript ES6 version. The ES6 version has brought many simplified improvements to JS. If you need it, What Is deconstruct assignment? Deconstruct value assignment allows you to assign values of arrays and objects to a series of variables using syntax similar to arrays or object literal values. This syntax is concise and clearer than tr

ES5 's top-level object itself is also a problem, because it is not unified in various implementations. Inside the browser, the top-level object is window , but Node and Web Worker do not window . Inside the browser and Web Worker, self It also points to the top-level object, but Node does not self . Node, the top-level object is global , but no other environment is supported. The same piece of code in order to be able to take the top-level objects in various environments,

1. ES6 string Changes(1) The includes () method returns False if the specified text in the string is detected to return true(2) The StartsWith () method returns True if the text is detected at the beginning of the string, otherwise false(3) The EndsWith () method returns True if text is detected at the end of the string, otherwise falseAll of the above methods receive two parameters, one is the text to be detected, the second parameter is optional, th

ES6 (ECMAScript 2015) coding specifications and detailed attention points, combined with a large number of GF securities ES6 practice projects organized,Already open from GitHub, continuous update, welcome PR and issue.GitHub Address: https://github.com/gf-web/es6-coding-style/This specification is based on the JavaScript specification and is only intended for

(This article also published in my public number "dotnet daily Essence article", Welcome to the right QR code to pay attention to. )Preface: the title is preface.Since the release of Visual Studio code (originally 0.1), Microsoft has been continuously updating it. The day before yesterday just released 0.5, bringing the following new features: File-handling updates, such as: Opening a file from the command line and locating to a specific line Enhancements to Editor Options Significan