{"id":13057,"date":"2021-01-24T14:54:36","date_gmt":"2021-01-24T05:54:36","guid":{"rendered":"http:\/\/www.code-magagine.com\/?p=13057"},"modified":"2023-09-05T08:27:55","modified_gmt":"2023-09-04T23:27:55","slug":"%e3%80%90react%e3%80%91%e3%80%8csrc-index-js%e3%80%8d%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6","status":"publish","type":"post","link":"http:\/\/www.code-magagine.com\/?p=13057","title":{"rendered":"\u3010React\u3011\u300csrc\/index.js\u300d\u306b\u3064\u3044\u3066"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">src\/index.js\u3068\u306f\uff1f<\/h2>\n\n\n\n<p>React\u306e\u30a8\u30f3\u30c8\u30ea\u30fc\u30dd\u30a4\u30f3\u30c8\uff08React\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5185\u3067\u4e00\u756a\u521d\u3081\u306b\u547c\u3073\u51fa\u3055\u308c\u308b\u30bd\u30fc\u30b9\uff09\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u307e\u305f\u3001webpack\u3068\u304b\u3092\u4f7f\u3063\u3066\u3044\u308b\u5834\u5408\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u3067webpack\u306e\u30a8\u30f3\u30c8\u30ea\u30fc\u30dd\u30a4\u30f3\u30c8\uff08\u30d3\u30eb\u30c9\u306e\u8d77\u70b9\uff09\u306b\u3082\u306a\u3063\u3066\u3044\u305f\u308a\u3057\u307e\u3059\u3002React\u30a2\u30d7\u30ea\u3092create-react-app\u3067\u4f5c\u3089\u308c\u3066\u3044\u308b\u5834\u5408\u306fwebpack\u306fcreate-react-app\u306b\u30e9\u30c3\u30d7\u3055\u308c\u3066\u3044\u308b\u306e\u3067\u610f\u8b58\u3057\u306a\u3044\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u304c\u3001\u5185\u90e8\u7684\u306a\u4ed5\u7d44\u307f\u306f\u901a\u5e38\u306eReact\u3068\u540c\u3058\u3067\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">import<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><th>import\u6587<\/th><th>\u8aac\u660e<\/th><\/tr><tr><td>\n<div>\n<div>import React from 'react';<\/div>\n<\/div>\n<\/td><td>React\u3092\u5229\u7528\u3059\u308b\u5834\u5408\u306f\u5fc5\u9808<\/td><\/tr><tr><td>\n<div>\n<div>import ReactDOM from 'react-dom';<\/div>\n<\/div>\n<\/td><td>HTML\u8981\u7d20\u306bApp\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u3092\u63cf\u753b\u3059\u308b\u5834\u5408\u5fc5\u8981<\/td><\/tr><tr><td>\n<div>\n<div>import App from '.\/App';<\/div>\n<\/div>\n<\/td><td>App\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u3092\u30a4\u30f3\u30dd\u30fc\u30c8\u3059\u308b\u3002<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">render<\/h2>\n\n\n\n<pre class=\"wp-block-preformatted\">ReactDOM.render(\n  &lt;React.StrictMode&gt;\n    &lt;App \/&gt;\n  &lt;\/React.StrictMode&gt;,\n  document.getElementById('root')\n);<\/pre>\n\n\n\n<ul>\n<li>App\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8(\u7b2c\u4e00\u5f15\u6570)\u3092&lt;div id=root&gt;&lt;\/div&gt;(\u7b2c\u4e8c\u5f15\u6570)\u306b\u63cf\u753b\u3057\u307e\u3059\u3002<\/li>\n\n\n\n<li>\u300csrc\/index.js\u300d\u306a\u3069\u304c\u30d3\u30eb\u30c9\u3055\u308c\u305fJavaScript\u30d5\u30a1\u30a4\u30eb\u306fpublic\/index.html\u3067\u8aad\u307f\u8fbc\u307e\u308c\u308b\u3002<\/li>\n\n\n\n<li>\u300cpublic\/index.html\u300d\u306e\u300c&lt;div id=\"root\"&gt;&lt;\/div&gt;\u300d\u306bApp\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u304c\u63cf\u753b\u3055\u308c\u308b\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">&lt;React.StrictMode&gt;<\/h3>\n\n\n\n<p>React16.3\u3067\u767b\u5834\u3057\u305f\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u3067\u3059\u3002React17\u3067\u30ec\u30f3\u30c0\u30ea\u30f3\u30b0\u306e\u975e\u540c\u671f\u5316\u304c\u5b9f\u88c5\u3055\u308c\u308b\u4e88\u5b9a\u306a\u306e\u3067\u3059\u304c\u3001\u305d\u306e\u524d\u306b\u30bd\u30fc\u30b9\u81ea\u4f53\u3092\u30c1\u30a7\u30c3\u30af\u3057\u3066\u304a\u3053\u3046\u3068\u3044\u3046\u76ee\u7684\u3067\u5c0e\u5165\u3055\u308c\u305f\u3088\u3046\u3067\u3059\u3002<\/p>\n\n\n\n<p>JavaScript\u81ea\u4f53\u306eStrict Mode\u3068\u540c\u3058\u3067\u4eca\u307e\u3067\u306e\u8a18\u8ff0\u65b9\u6cd5\u306b\u554f\u984c\u304c\u3042\u308b\u5834\u5408\u306f\u305d\u308c\u3092\u7099\u308a\u51fa\u3057\u3066\u304f\u308c\u307e\u3059\u3002\uff08\u5177\u4f53\u7684\u306b\u306f\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u306e\u30d0\u30b0\u691c\u77e5\u3001\u4e88\u671f\u305b\u306c\u51e6\u7406\u3092\u8b66\u544a\u3057\u3066\u304f\u308c\u305f\u308a\u3059\u308b\u3002\uff09\u306a\u304a\u3001production\u30d3\u30eb\u30c9\u3067\u306f\u3053\u306e\u691c\u67fb\u304c\u52d5\u4f5c\u305b\u305a\u3001development\u30d3\u30eb\u30c9\u3067\u306f\u52d5\u4f5c\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u307e\u305f\u3001React18\u304b\u3089\u306f\u958b\u767a\u30e2\u30fc\u30c9\u3060\u3068Strict\u3092\u6709\u52b9\u306b\u3057\u3066\u3044\u308b\u30682\u56de\u30de\u30a6\u30f3\u30c8\u3055\u308c\u3066\u3057\u307e\u3046\u73fe\u8c61\u304c\u767a\u751f\u3059\u308b\u306e\u3067\u3082\u3057\u518d\u30ec\u30f3\u30c0\u30ea\u30f3\u30b0\u306e\u5bfe\u7b56\u306a\u3069\u3092\u3055\u308c\u305f\u3044\u5834\u5408\u306a\u3069\u306f\u3053\u3061\u3089\u306e\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u306f\u524a\u9664\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u53c2\u8003\uff1aJavaScript\u306estrict\u30e2\u30fc\u30c9<\/h2>\n\n\n\n<p>JavaScript\u306b\u306f\u904e\u53bb\u306e\u30b3\u30fc\u30c9\u3092\u52d5\u304b\u305b\u308b\u3088\u3046\u306b\u3057\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3068\u3044\u3046\u6697\u9ed9\u306e\u30eb\u30fc\u30eb\u304c\u3042\u308a\u307e\u3059\u3002\u305f\u3060\u3001\u904e\u53bb\u306e\u30b3\u30fc\u30c9\u3092\u52d5\u304b\u3057\u3066\u306a\u304a\u304b\u3064\u8a00\u8a9e\u306e\u4e0d\u5099\u3092\u6539\u5584\u3059\u308b\u30e2\u30fc\u30c9\u304c\u3042\u308a\u307e\u3059\u3002\u305d\u308c\u304c\u300cstrict\u30e2\u30fc\u30c9\u300d\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u5ba3\u8a00\u65b9\u6cd5<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u30b9\u30af\u30ea\u30d7\u30c8\u5168\u4f53\u306b\u9069\u7528<\/h4>\n\n\n\n<pre class=\"wp-block-preformatted\">&lt;script&gt;\n'use strict';\n&lt;\/script&gt;<\/pre>\n\n\n\n<p>1\u756a\u4e0a\u306b\u3053\u308c\u3092\u5ba3\u8a00\u3057\u305f\u3089\u3053\u308c\u4ee5\u4e0b\u306e\u6587\u306f\u5168\u3066strict\u30e2\u30fc\u30c9\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">\u6ce8\u610f\u70b9<\/h5>\n\n\n\n<p>2\u884c\u76ee\u4ee5\u964d\u306b\u8a18\u8ff0\u3057\u305f\u3089\u4e00\u5207strict\u30e2\u30fc\u30c9\u306b\u306f\u306a\u3089\u306a\u304f\u306a\u308a\u307e\u3059\u3002\u5fc5\u305a1\u884c\u76ee\u306b\u8a18\u8ff0\u3059\u308b\u3088\u3046\u306b\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<p>\u307e\u305f\u3001script\u30bf\u30b0\u3054\u3068\u306b\u9069\u7528\u3055\u308c\u308b\u306e\u3067\u8907\u6570\u306escript\u30bf\u30b0\u3092\u4f7f\u3046\u5834\u5408\u306f\u5168\u3066\u306escript\u30bf\u30b0\u3054\u3068\u306bstrict\u30e2\u30fc\u30c9\u306e\u5ba3\u8a00\u3092\u3059\u308b\u3088\u3046\u306b\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u7279\u5b9a\u306e\u95a2\u6570\u3060\u3051\u306b\u9069\u7528<\/h4>\n\n\n\n<p>\u95a2\u6570\u306e1\u884c\u76ee\u306b\u5ba3\u8a00\u3059\u308b\u3053\u3068\u3067\u305d\u306e\u95a2\u6570\u3060\u3051\u306bstrict\u30e2\u30fc\u30c9\u3092\u9069\u7528\u3059\u308b\u3053\u3068\u304c\u53ef\u80fd\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">function add(a, b) {\n  'use strict'\n  return a + b;\n};<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u5177\u4f53\u7684\u306b\u3069\u3046\u306a\u308b\u306e\u304b\uff1f<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95a2\u6570\u5ba3\u8a00\u6587\u304c\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u306b\u306a\u308b\u3002<\/h4>\n\n\n\n<p>\u904e\u53bb\u306eJS\u3067\u306f\u95a2\u6570\u5ba3\u8a00\u306f\u30b0\u30ed\u30fc\u30d0\u30eb\u30b9\u30b3\u30fc\u30d7\u3060\u3063\u305f\u306e\u3067\u30b9\u30b3\u30fc\u30d7\u306e\u7bc4\u56f2\u304c\u72ed\u307e\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">var\u3001let\u3001const\u304c\u306a\u3044\u3068\u5909\u6570\u5ba3\u8a00\u304c\u3067\u304d\u306a\u304f\u306a\u308b\u3002<\/h4>\n\n\n\n<p>\u904e\u53bb\u306eJS\u3067\u3042\u308c\u3070var\u304c\u306a\u304f\u3066\u3082\u5909\u6570\u5ba3\u8a00\u3067\u304d\u307e\u3057\u305f\u3002\u666e\u901a\u306b\u30b0\u30ed\u30fc\u30d0\u30eb\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u7d44\u307f\u8fbc\u307e\u308c\u305f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"src\/index.js\u3068\u306f\uff1f React\u306e\u30a8\u30f3\u30c8\u30ea\u30fc\u30dd\u30a4\u30f3\u30c8\uff08React\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u5185\u3067\u4e00\u756a\u521d\u3081\u306b\u547c\u3073\u51fa\u3055\u308c\u308b\u30bd\u30fc\u30b9\uff09\u3067\u3059\u3002 \u307e\u305f\u3001webpack\u3068\u304b\u3092\u4f7f\u3063\u3066\u3044\u308b\u5834\u5408\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u3067webpack\u306e\u30a8\u30f3\u30c8\u30ea\u30fc\u30dd\u30a4\u30f3\u30c8 [&hellip;]","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[116],"tags":[],"_links":{"self":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts\/13057"}],"collection":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=13057"}],"version-history":[{"count":6,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts\/13057\/revisions"}],"predecessor-version":[{"id":22408,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts\/13057\/revisions\/22408"}],"wp:attachment":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=13057"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=13057"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=13057"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}