Do all browsers now support es6?-Common Problem-php.cn

Home

Common Problem

Do all browsers now support es6?

青灯夜游

Oct 20, 2022 pm 02:20 PM

es6

No; ES6 provides many new features, but not all browsers can perfectly support it. For example, IE7~11 versions basically do not support ES6, and Edge12-14 only supports some of the new ES6 features; for ES6 The most user-friendly browsers with new features are Chrome and Firefox. Chrome can support 97% of ES6 new features starting from version 51, and Firefox can support 97% of ES6 new features starting from version 53.

Do all browsers now support es6?

The operating environment of this tutorial: Windows 7 system, ECMAScript version 6, Dell G3 computer.

ES6 provides many new features, but not all browsers can fully support them. Fortunately, major browsers are now accelerating their compatibility with the new features of ES6. Among them, the most friendly browsers for the new features of ES6 are Chrome and Firefox.

Introduction to browser compatibility of ES6 syntax

##12-1415-18 ,79-87Firefox2-56-5354-86Chrome4-2021-5051-90Safari3.1-77.1-9.110-13.1, 14, TP##Opera##iOS Safari7-9.310-13.7, 14.2Opera Mini##Android Browser12-12.1Chrome for Android##83Samsung Internet45-13.0 ##10.4##7.12##

For details on each browser’s support for ES6, please check https://caniuse.com/?search=es6

If you want to know whether your browser supports ES6, please check http:// ruanyf.github.io/es-checker/index.cn.html

Desktop browser support for ES2015

Chrome: Starting from version 51, it can support 97% of the new features of ES6.
Firefox: Supports 97% of ES6 new features starting from version 53.
Safari: Supports 99% of ES6 new features starting from version 10.
IE: Edge 15 can support 96% of the new ES6 features.
Edge 14 can support 93% of the new ES6 features. (IE7~11 basically does not support ES6)

It can be seen that IE11 is dragging its feet again, completely giving up on ES6, and Edge will support its future.

IE11 is effectively compatible with ES6

So how do you make pure ES6 scripts run under IE11? Babel provides an effective solution.

Introduce two scripts:

https://cdn.bootcss.com/babel-core/5.8.35/browser.min.js

The The script converts statements at the es6 syntax level

https://cdn.bootcss.com/babel-core/5.8.35/browser-polyfill.min.js

This script converts the new syntax API, such as Set Map Promise, etc. methods

Mark the script blocktype = "text/babel"

<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>IE11 With ES6</title>
    <script src="./browser-polyfill.min.js"></script>
    <script src="./browser.min.js"></script>
    <script type="text/babel">
        const list = [&#39;one&#39;, &#39;two&#39;, &#39;three&#39;];
        list.forEach((item, index) => {
            alert(item + (index + 1));
        });


        let promise = new Promise(function (resolve, reject) {
            alert(&#39;Promise&#39;);
            resolve();
        });

        promise.then(function () {
            alert(&#39;resolved.&#39;);
        });


        const items = new Set([1, 2, 3, 4, 5, 5, 5, 5]);
        alert(items.size)


        const map = new Map();

        const k1 = [&#39;a&#39;];
        const k2 = [&#39;a&#39;];

        map.set(k1, 111).set(k2, 222);

        alert(map.get(k2))

    </script>
</head>

<body>

</body>

</html>

Copy after login

So there are two confusions here:

First: <script type="text/babel"> and the &lt we usually use ;script type="text/javascript">What is the difference.

Second: What exactly does polyfill do?

Let’s explain it separately. Let’s look at an uncompressed code: https://cdn.bootcss.com/babel-core/5.8 .38/browser.js
Found the following code snippets:

//页面加载后，执行runScripts方法
if (global.addEventListener) {
  global.addEventListener("DOMContentLoaded", runScripts, false);
} else if (global.attachEvent) {
  global.attachEvent("onload", runScripts);
}

Copy after login

var runScripts = function runScripts() {
  var scripts = [];
  //识别类型
  var types = ["text/ecmascript-6", "text/6to5", "text/babel", "module"];
  var index = 0;

  /**
   * Transform and execute script. Ensures correct load order.
   */

  var exec = function exec() {
    var param = scripts[index];
    if (param instanceof Array) {
      transform.run.apply(transform, param);
      index++;
      exec();
    }
  };

  /**
   * Load, transform, and execute all scripts.
   */

  var run = function run(script, i) {
    var opts = {};

    if (script.src) {
      transform.load(script.src, function (param) {
        scripts[i] = param;
        exec();
      }, opts, true);
    } else {
      opts.filename = "embedded";
      scripts[i] = [script.innerHTML, opts];
    }
  };

  // Collect scripts with Babel `types`.

  var _scripts = global.document.getElementsByTagName("script");
  //按照类别加载
  for (var i = 0; i < _scripts.length; ++i) {
    var _script = _scripts[i];
    if (types.indexOf(_script.type) >= 0) scripts.push(_script);
  }
  //执行
  for (i in scripts) {
    run(scripts[i], i);
  }

  exec();
};

Copy after login

I think the text/babel we are paying attention to is here: var types = ["text/ecmascript-6", "text/ 6to5", "text/babel", "module"];

Get the steps marked with the above three items on the page, and then use the transform library to load and translate them into ES5 for execution.

So what does polyfill do? Continue reading the code https://cdn.bootcss.com/babel-core/5.8.38/browser-polyfill.js
Also locate a piece of code:

$export($export.P, &#39;Array&#39;, {
  // 22.1.3.10 / 15.4.4.18 Array.prototype.forEach(callbackfn [, thisArg])
  forEach: $.each = $.each || methodize(createArrayMethod(0)),
  // 22.1.3.15 / 15.4.4.19 Array.prototype.map(callbackfn [, thisArg])
  map: methodize(createArrayMethod(1)),
  // 22.1.3.7 / 15.4.4.20 Array.prototype.filter(callbackfn [, thisArg])
  filter: methodize(createArrayMethod(2)),
  // 22.1.3.23 / 15.4.4.17 Array.prototype.some(callbackfn [, thisArg])
  some: methodize(createArrayMethod(3)),
  // 22.1.3.5 / 15.4.4.16 Array.prototype.every(callbackfn [, thisArg])
  every: methodize(createArrayMethod(4)),
  // 22.1.3.18 / 15.4.4.21 Array.prototype.reduce(callbackfn [, initialValue])
  reduce: createArrayReduce(false),
  // 22.1.3.19 / 15.4.4.22 Array.prototype.reduceRight(callbackfn [, initialValue])
  reduceRight: createArrayReduce(true),
  // 22.1.3.11 / 15.4.4.14 Array.prototype.indexOf(searchElement [, fromIndex])
  indexOf: methodize(arrayIndexOf),
  // 22.1.3.14 / 15.4.4.15 Array.prototype.lastIndexOf(searchElement [, fromIndex])
  lastIndexOf: function(el, fromIndex /* = @[*-1] */){
    var O      = toIObject(this)
      , length = toLength(O.length)
      , index  = length - 1;
    if(arguments.length > 1)index = Math.min(index, toInteger(fromIndex));
    if(index < 0)index = toLength(length + index);
    for(;index >= 0; index--)if(index in O)if(O[index] === el)return index;
    return -1;
  }
});


var createArrayReduce = function(isRight){
  return function(callbackfn, memo){
    aFunction(callbackfn);
    var O      = IObject(this)
      , length = toLength(O.length)
      , index  = isRight ? length - 1 : 0
      , i      = isRight ? -1 : 1;
    if(arguments.length < 2)for(;;){
      if(index in O){
        memo = O[index];
        index += i;
        break;
      }
      index += i;
      if(isRight ? index < 0 : length <= index){
        throw TypeError(&#39;Reduce of empty array with no initial value&#39;);
      }
    }
    for(;isRight ? index >= 0 : length > index; index += i)if(index in O){
      memo = callbackfn(memo, O[index], index, this);
    }
    return memo;
  };
};

Copy after login

You can find that ployfill adds many new methods to Arrary, such as createArrayReduce, which is used to implement reduce.

Note

Introducing the above two files basically solves most of the browser's support for ES6.

But again: Even if you use a conversion tool, it is not recommended to use a large number of new features that have low browser support for ES6 in a production environment. After all, this is performed after online conversion, and the efficiency is relatively low. Moreover, as browser support for ES6 changes, these conversion scripts also need to be updated frequently, which will inevitably have an impact on later maintenance.

【Related recommendations: javascript video tutorial, programming video】

Browser	Unsupported version	Partially supported versions	Supported versions
IE	6-10	11
Edge



10-12.1	15-37	38-72
3.2-6.1
all
2.1-4.34.4-4.4 .4	81		##Opera Mobile
	59
	##87	Firefox for Android
		UC Browser for Android
##12.12
	QQ Browser
	Baidu Browser
	KaiOS Browser		2.5

The above is the detailed content of Do all browsers now support es6?. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress images for free

Clothoff.io

AI clothes remover

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)

4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

R.E.P.O. Best Graphic Settings

4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Assassin's Creed Shadows: Seashell Riddle Solution

2 weeks ago By DDD

R.E.P.O. How to Fix Audio if You Can't Hear Anyone

4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

WWE 2K25: How To Unlock Everything In MyRise

1 months ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Where is the login entrance for gmail email?

7504

CakePHP Tutorial

1378

What is the format of the account name of steam

win11 activation key permanent

nyt connections hints and answers

Related knowledge

How to reverse an array in ES6 Oct 26, 2022 pm 06:19 PM

In ES6, you can use the reverse() method of the array object to achieve array reversal. This method is used to reverse the order of the elements in the array, putting the last element first and the first element last. The syntax "array.reverse()". The reverse() method will modify the original array. If you do not want to modify it, you need to use it with the expansion operator "...", and the syntax is "[...array].reverse()".

Is async for es6 or es7? Jan 29, 2023 pm 05:36 PM

async is es7. async and await are new additions to ES7 and are solutions for asynchronous operations; async/await can be said to be syntactic sugar for co modules and generator functions, solving js asynchronous code with clearer semantics. As the name suggests, async means "asynchronous". Async is used to declare that a function is asynchronous; there is a strict rule between async and await. Both cannot be separated from each other, and await can only be written in async functions.

How to find different items in two arrays in es6 Nov 01, 2022 pm 06:07 PM

Steps: 1. Convert the two arrays to set types respectively, with the syntax "newA=new Set(a);newB=new Set(b);"; 2. Use has() and filter() to find the difference set, with the syntax " new Set([...newA].filter(x =>!newB.has(x)))", the difference set elements will be included in a set collection and returned; 3. Use Array.from to convert the set into an array Type, syntax "Array.from(collection)".

Why does the mini program need to convert es6 to es5? Nov 21, 2022 pm 06:15 PM

For browser compatibility. As a new specification for JS, ES6 adds a lot of new syntax and API. However, modern browsers do not have high support for the new features of ES6, so ES6 code needs to be converted to ES5 code. In the WeChat web developer tools, babel is used by default to convert the developer's ES6 syntax code into ES5 code that is well supported by all three terminals, helping developers solve development problems caused by different environments; only in the project Just configure and check the "ES6 to ES5" option.

How to implement array deduplication in es5 and es6 Jan 16, 2023 pm 05:09 PM

In es5, you can use the for statement and indexOf() function to achieve array deduplication. The syntax "for(i=0;i<array length;i++){a=newArr.indexOf(arr[i]);if(a== -1){...}}". In es6, you can use the spread operator, Array.from() and Set to remove duplication; you need to first convert the array into a Set object to remove duplication, and then use the spread operator or the Array.from() function to convert the Set object back to an array. Just group.

What does es6 temporary Zenless Zone Zero mean? Jan 03, 2023 pm 03:56 PM

In es6, the temporary dead zone is a syntax error, which refers to the let and const commands that make the block form a closed scope. Within a code block, before a variable is declared using the let/const command, the variable is unavailable and belongs to the variable's "dead zone" before the variable is declared; this is syntactically called a "temporary dead zone". ES6 stipulates that variable promotion does not occur in temporary dead zones and let and const statements, mainly to reduce runtime errors and prevent the variable from being used before it is declared, resulting in unexpected behavior.

Is require an es6 syntax? Oct 21, 2022 pm 04:09 PM

No, require is the modular syntax of the CommonJS specification; and the modular syntax of the es6 specification is import. require is loaded at runtime, and import is loaded at compile time; require can be written anywhere in the code, import can only be written at the top of the file and cannot be used in conditional statements or function scopes; module attributes are introduced only when require is run. Therefore, the performance is relatively low. The properties of the module introduced during import compilation have slightly higher performance.

Is es6 map ordered? Nov 03, 2022 pm 07:05 PM

The map is ordered. The map type in ES6 is an ordered list that stores many key-value pairs. The key names and corresponding values support all data types; the equivalence of key names is determined by calling the "Objext.is()" method. Implemented, so the number 5 and the string "5" will be judged as two types, and can appear in the program as two independent keys.