{"id":4269,"date":"2024-02-29T20:00:57","date_gmt":"2024-02-29T11:00:57","guid":{"rendered":"https:\/\/www.bold.ne.jp\/engineer-club\/?p=4269"},"modified":"2025-12-19T11:29:05","modified_gmt":"2025-12-19T02:29:05","slug":"javascript-foreach","status":"publish","type":"post","link":"https:\/\/www.bold.ne.jp\/engineer-club\/javascript-foreach","title":{"rendered":"JavaScript\u306eforEach\u3068\u306f\uff1f\u52b9\u7387\u7684\u306b\u914d\u5217\u306e\u8981\u7d20\u3092\u9806\u306b\u53d6\u308a\u51fa\u3059\u65b9\u6cd5"},"content":{"rendered":"<p>JavaScript\u3067\u914d\u5217\u306e\uff11\u3064\uff11\u3064\u306e\u8981\u7d20\u3092\u30eb\u30fc\u30d7\u51e6\u7406\u3067\u9806\u306b\u53d6\u308a\u51fa\u3057\u3066\u51e6\u7406\u3092\u884c\u306a\u3046\u6642\u306b\u7528\u3044\u3089\u308c\u308b\u30e1\u30bd\u30c3\u30c9\u306e\uff11\u3064\u3068\u3057\u3066\u3001forEach\u30e1\u30bd\u30c3\u30c9\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<p>\u901a\u5e38\u30eb\u30fc\u30d7\u51e6\u7406\u3092\u884c\u306a\u3046\u6642\u306ffor\u6587\u304c\u7528\u3044\u3089\u308c\u308b\u3053\u3068\u304c\u591a\u3044\u304b\u3068\u601d\u3044\u307e\u3059\u304c\u3001forEach\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3046\u3053\u3068\u3067for\u6587\u3088\u308a\u3082\u30b7\u30f3\u30d7\u30eb\u306a\u30b3\u30fc\u30c9\u3067\u51e6\u7406\u3092\u8a18\u8ff0\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u672c\u8a18\u4e8b\u3067\u306f\u3001<strong><span class=\"f-marker-p\">forEach\u30e1\u30bd\u30c3\u30c9\u306e\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9<\/span><\/strong>\u3084<strong><\/strong><span class=\"f-marker-p\"><strong>\u3069\u306e\u3088\u3046\u306a\u51e6\u7406\u3092\u884c\u306a\u3046\u3053\u3068\u304c\u3067\u304d\u308b\u304b<\/strong><\/span>\u306b\u3064\u3044\u3066\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n<div id=\"toc_container\" class=\"no_bullets\"><p class=\"toc_title\">\u76ee\u6b21<\/p><ul class=\"toc_list\"><li><a href=\"#JavaScriptforEach\">\uff11\uff0eJavaScript\u306eforEach\u30e1\u30bd\u30c3\u30c9\u306e\u57fa\u672c\u69cb\u6587<\/a><ul><li><a href=\"#-forEach\">\uff11-\uff11\uff0eforEach\u30e1\u30bd\u30c3\u30c9\u306e\u4f7f\u7528\u4f8b<\/a><\/li><li><a href=\"#-for\">\uff11-\uff12\uff0efor\u6587\u3068\u306e\u6bd4\u8f03<\/a><\/li><li><a href=\"#i\">\uff11-\uff13\uff0e\u5f15\u6570\u306e\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306b\u8907\u6570\u306e\u5f15\u6570\u3092\u6307\u5b9a\u3059\u308b\u4f8b<\/a><\/li><\/ul><\/li><li><a href=\"#JavaScript_forEach\">\uff12\uff0eJavaScript forEach\u30e1\u30bd\u30c3\u30c9\u306e\u5fdc\u7528\u4f8b<\/a><ul><li><a href=\"#i-2\">\uff12-\uff11\uff0e\u5f15\u6570\u306e\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u3092\u30a2\u30ed\u30fc\u95a2\u6570\u3067\u8a18\u8ff0<\/a><\/li><li><a href=\"#i-3\">\uff12-\uff12\uff0e\u5225\u3067\u5b9a\u7fa9\u3057\u305f\u95a2\u6570\u3092\u5f15\u6570\u306b\u6307\u5b9a<\/a><\/li><li><a href=\"#-forEach-2\">\uff12-\uff13\uff0eforEach\u30e1\u30bd\u30c3\u30c9\u306e\u7b2c\uff12\u5f15\u6570\u306b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u6e21\u3059\u4f8b<\/a><\/li><\/ul><\/li><li><a href=\"#JavaScript_forEach-2\">\uff13\uff0eJavaScript forEach\u30e1\u30bd\u30c3\u30c9\u306e\u6ce8\u610f\u70b9<\/a><ul><li><a href=\"#-continuebreak\">\uff13-\uff11\uff0econtinue\u306b\u3088\u308b\u51e6\u7406\u306e\u4e2d\u65ad\u3084break\u306b\u3088\u308b\u629c\u3051\u51fa\u3057\u304c\u3067\u304d\u306a\u3044<\/a><\/li><li><a href=\"#i-4\">\uff13-\uff12\uff0e\u4ed6\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u7528\u3044\u308b\u65b9\u304c\u9069\u5207\u306a\u5834\u9762\u304c\u3042\u308b<\/a><\/li><\/ul><\/li><li><a href=\"#i-5\">\uff14\uff0e\u6700\u5f8c\u306b<\/a><\/li><\/ul><\/div>\n<h2><span id=\"JavaScriptforEach\"><strong>\uff11\uff0eJavaScript\u306eforEach<\/strong><strong>\u30e1\u30bd\u30c3\u30c9\u306e\u57fa\u672c\u69cb\u6587<\/strong><\/span><\/h2>\n<p>JavaScript\u306eforEach\u30e1\u30bd\u30c3\u30c9\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u8a18\u8ff0\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">\u914d\u5217\u540d.forEach(\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570(\u914d\u5217\u306e\u8981\u7d20));<\/pre>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u306f\u914d\u5217\u306e\u8981\u7d20\u3092\u5148\u982d\u304b\u3089\u9806\u306b\u53d6\u308a\u51fa\u3057\u3001\u5f15\u6570\u306b\u6307\u5b9a\u3057\u305f\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u3092\u547c\u3073\u51fa\u3057\u307e\u3059\u3002\u5f8c\u8ff0\u3057\u307e\u3059\u304c\u3001\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u5f15\u6570\u3068\u3057\u3066\u300c\u914d\u5217\u306e\u8981\u7d20\u306e\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u300d\u3084\u300c\u914d\u5217\u81ea\u8eab\u300d\u3092\u4efb\u610f\u3067\u8ffd\u52a0\u3057\u3066\u6307\u5b9a\u3059\u308b\u3053\u3068\u3082\u53ef\u80fd\u3067\u3059\u3002<\/p>\n<h3><span id=\"-forEach\">\uff11-\uff11\uff0e<strong>forEach\u30e1\u30bd\u30c3\u30c9\u306e\u4f7f\u7528\u4f8b<\/strong><\/span><\/h3>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3063\u3066\u914d\u5217\u306e\u8981\u7d20\u3092\u9806\u756a\u306b\u51fa\u529b\u3059\u308b\u4f8b\u3092\u4ee5\u4e0b\u306b\u793a\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const fruits = [\u2018Apple\u2019, \u2018Banana\u2019, \u2018Cherry\u2019];\r\n\r\nfruits.forEach(function(fruit){\r\n     console.log(fruit);\r\n});\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ Apple\r\n\/\/ Banana\r\n\/\/ Cherry<\/pre>\n<p>\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u5f15\u6570\u306b\u6307\u5b9a\u3057\u305ffruit\u306b\u914d\u5217fruits\u306e\u8981\u7d20\u3067\u3042\u308b<span>\u2018<\/span>Apple\u2019, \u2018Banana\u2019, \u2018Cherry\u2019\u304c\u9806\u756a\u306b\u5165\u308a\u3001\uff11\u3064\u305a\u3064\u51fa\u529b\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n<h3><span id=\"-for\"><strong>\uff11-\uff12\uff0efor<\/strong><strong>\u6587\u3068\u306e\u6bd4\u8f03<\/strong><\/span><\/h3>\n<p>1-1.\u306e\u4f8b\u3092for\u6587\u3067\u8a18\u8ff0\u3059\u308b\u3068\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const fruits = [\u2018Apple\u2019, \u2018Banana\u2019, \u2018Cherry\u2019];\r\n\r\nfor(var i = 0; i &lt; fruits.length; i++){\r\n     console.log(fruits[i]);\r\n}\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ Apple\r\n\/\/ Banana\r\n\/\/ Cherry<\/pre>\n<p>for\u6587\u3067\u306f\u7e70\u308a\u8fd4\u3057\u306e\u30ab\u30a6\u30f3\u30bf\u30fc\uff08i\uff09\u3084\u30eb\u30fc\u30d7\u306e\u7e70\u308a\u8fd4\u3057\u6761\u4ef6\uff08i &lt; fruits.length\uff09\u3001\u30ab\u30a6\u30f3\u30bf\u30fc\u306e\u66f4\u65b0\uff08i++\uff09\u3092\u6307\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u30ab\u30a6\u30f3\u30bf\u30fc\u306ei\u3092\u914d\u5217\u306e\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u756a\u53f7\u3068\u3057\u3066\u3001\u914d\u5217fruits\u306e\u4e2d\u8eab\u3092\u9806\u756a\u306b\u53c2\u7167\u3059\u308b\u3053\u3068\u3067\u540c\u3058\u7d50\u679c\u3068\u306a\u3063\u3066\u3044\u307e\u3059\u3002<\/p>\n<p>\u305f\u3060\u3057\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u914d\u5217\u306e\u9014\u4e2d\u306e\u8981\u7d20\u304c\u306a\u3044\u5834\u5408\u306f\u7570\u306a\u308b\u7d50\u679c\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const fruits = [\u2018Apple\u2019, \u2018Banana\u2019, , , \u2018Cherry\u2019];\r\n\r\n\/\/ forEach\u30e1\u30bd\u30c3\u30c9\r\nfruits.forEach(function(fruit){\r\n     console.log(fruit);\r\n});\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ Apple\r\n\/\/ Banana\r\n\/\/ Cherry\r\n\r\n\/\/ for\u6587\r\nfor(var i = 0; i &lt; fruits.length; i++){\r\n     console.log(fruits[i]);\r\n}\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ Apple\r\n\/\/ Banana\r\n\/\/ undefined\r\n\/\/ undefined\r\n\/\/ Cherry<\/pre>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u3067\u306f\u8981\u7d20\u304c\u306a\u3044\u5834\u5408\u51e6\u7406\u304c\u30b9\u30ad\u30c3\u30d7\u3055\u308c\u307e\u3059\u304c\u3001for\u6587\u3067\u306f\u30b9\u30ad\u30c3\u30d7\u305b\u305a\u306b\u51e6\u7406\u3055\u308c\u308b\u305f\u3081\u3001\u8981\u7d20\u304c\u672a\u5b9a\u7fa9\u3067\u3042\u308b\u3053\u3068\u3092\u8868\u3059undefined\u304c\u51fa\u529b\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n<h3><span id=\"i\"><strong>\uff11-\uff13\uff0e<\/strong><strong>\u5f15\u6570\u306e\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306b\u8907\u6570\u306e\u5f15\u6570\u3092\u6307\u5b9a\u3059\u308b\u4f8b<\/strong><\/span><\/h3>\n<p>\u524d\u8ff0\u3057\u305f\u901a\u308a\u3001\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u5f15\u6570\u3068\u3057\u3066\u300c\u914d\u5217\u306e\u8981\u7d20\u306e\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u300d\u3084\u300c\u914d\u5217\u81ea\u8eab\u300d\u3092\u4efb\u610f\u3067\u6307\u5b9a\u3059\u308b\u3053\u3068\u3082\u53ef\u80fd\u3067\u3059\u3002<\/p>\n<h4><strong>\uff11-\uff13-\uff11\uff0e\uff12<\/strong><strong>\u3064\u306e\u5f15\u6570\u3092\u6307\u5b9a<\/strong><\/h4>\n<p>\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306b\u5f15\u6570\u3092\uff12\u3064\u6307\u5b9a\u3059\u308b\u3068\u304d\u306f\u3001\u300c\u914d\u5217\u306e\u8981\u7d20\u300d\u3068\u300c\u914d\u5217\u306e\u8981\u7d20\u306e\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u300d\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002\u4ee5\u4e0b\u306b\u4f7f\u7528\u4f8b\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const numbers = [1, 2, 3];\r\n\r\nnumbers.forEach(function(number, index){\r\n     console.log(\u201cnumbers[\u201d + index + \u201c] : \u201c + number);\r\n});\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ numbers[0] : 1\r\n\/\/ numbers[1] : 2\r\n\/\/ numbers[2] : 3\r\n<\/pre>\n<p>\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u5f15\u6570\u306b\u6307\u5b9a\u3057\u305fnumber\u306b\u914d\u5217numbers\u306e\u8981\u7d20\u3067\u3042\u308b1, 2, 3\u304c\u3001index\u306b\u306f\u914d\u5217numbers\u306e\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u756a\u53f7\u3067\u3042\u308b0, 1, 2\u304c\u9806\u756a\u306b\u5165\u308a\u3001\u305d\u308c\u305e\u308c\u51fa\u529b\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n<h4><strong>\uff11-\uff13-\uff12\uff0e<\/strong><strong>\uff13\u3064\u306e\u5f15\u6570\u3092\u6307\u5b9a<\/strong><\/h4>\n<p>\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306b\u5f15\u6570\u3092\uff13\u3064\u6307\u5b9a\u3059\u308b\u3068\u304d\u306f\u3001\u300c\u914d\u5217\u306e\u8981\u7d20\u300d\u300c\u914d\u5217\u306e\u8981\u7d20\u306e\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u300d\u300c\u914d\u5217\u81ea\u8eab\u300d\u3092\u6307\u5b9a\u3057\u307e\u3059\u3002\u4ee5\u4e0b\u306b\u4f7f\u7528\u4f8b\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">var numbers = [1, 2, 3];\r\n\r\nnumbers.forEach(function(number, index, array){\r\n     array[index] = number * 2;\r\n     console.log(array[index]);\r\n});\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ 2\r\n\/\/ 4\r\n\/\/ 6\r\n<\/pre>\n<p>\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u5f15\u6570\u306b\u6307\u5b9a\u3057\u305farray\u306f\u914d\u5217numbers\u81ea\u8eab\u3092\u8868\u3057\u3066\u304a\u308a\u3001\u51e6\u7406\u306e\u4e2d\u3067\u305d\u308c\u305e\u308c\u306e\u8981\u7d20\u3092\uff12\u500d\u3059\u308b\u3053\u3068\u3067\u914d\u5217numbers\u3092\u66f4\u65b0\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<h2><span id=\"JavaScript_forEach\"><strong>\uff12\uff0eJavaScript forEach<\/strong><strong>\u30e1\u30bd\u30c3\u30c9\u306e\u5fdc\u7528\u4f8b<\/strong><\/span><\/h2>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u306e\u5fdc\u7528\u4f8b\u3092\u3044\u304f\u3064\u304b\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n<h3><span id=\"i-2\"><strong>\uff12-\uff11\uff0e<\/strong><strong>\u5f15\u6570\u306e\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u3092\u30a2\u30ed\u30fc\u95a2\u6570\u3067\u8a18\u8ff0<\/strong><\/span><\/h3>\n<p>\u5f15\u6570\u306e\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306f\u30a2\u30ed\u30fc\u95a2\u6570\u3067\u8a18\u8ff0\u3059\u308b\u3053\u3068\u3082\u53ef\u80fd\u3067\u3059\u3002\u4f8b\u3048\u30701-1.\u306e\u4f8b\u306f\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u66f8\u304d\u63db\u3048\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const fruits = [\u2018Apple\u2019, \u2018Banana\u2019, \u2018Cherry\u2019];\r\n\r\nfruits.forEach((fruit) =&gt; console.log(fruit));\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ Apple\r\n\/\/ Banana\r\n\/\/ Cherry\r\n<\/pre>\n<p>\u30a2\u30ed\u30fc\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u30b7\u30f3\u30d7\u30eb\u306b\u8a18\u8ff0\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u30021-3-2.\u306e\u3088\u3046\u306b\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u51e6\u7406\u304c\u8907\u6570\u884c\u3042\u308b\u5834\u5408\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u51e6\u7406\u306e\u7b87\u6240\u3092{}\u3067\u56f2\u3044\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">var numbers = [1, 2, 3];\r\n\r\nnumbers.forEach((number, index, array) =&gt; {\r\n     array[index] = number * 2;\r\n     console.log(array[index]);\r\n});\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ 2\r\n\/\/ 4\r\n\/\/ 6\r\n<\/pre>\n<h3><span id=\"i-3\"><strong>\uff12-\uff12\uff0e<\/strong><strong>\u5225\u3067\u5b9a\u7fa9\u3057\u305f\u95a2\u6570\u3092\u5f15\u6570\u306b\u6307\u5b9a<\/strong><\/span><\/h3>\n<p>\u5f15\u6570\u306b\u76f4\u63a5\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u51e6\u7406\u3092\u8a18\u8ff0\u305b\u305a\u3068\u3082\u3001\u5225\u3067\u5b9a\u7fa9\u3057\u305f\u95a2\u6570\u3092\u5f15\u6570\u306b\u6307\u5b9a\u3057\u3066\u51e6\u7406\u3092\u884c\u3046\u3053\u3068\u3082\u53ef\u80fd\u3067\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const fruits = [\u2018Apple\u2019, \u2018Banana\u2019, \u2018Cherry\u2019];\r\n\r\nfunction output(str) {\r\n     console.log(str);\r\n};\r\n\r\nfruits.forEach(output);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ Apple\r\n\/\/ Banana\r\n\/\/ Cherry\r\n<\/pre>\n<p>\u5f15\u6570\u306e\u5024\u3092\u51fa\u529b\u3059\u308b\u95a2\u6570output\u306e\u95a2\u6570\u540d\u3092forEach\u30e1\u30bd\u30c3\u30c9\u306e\u5f15\u6570\u306b\u6307\u5b9a\u3059\u308b\u3053\u3068\u3067\u3001\u5225\u3067\u5b9a\u7fa9\u3057\u305f\u95a2\u6570\u3092\u547c\u3073\u51fa\u3057\u3066\u51e6\u7406\u3092\u884c\u3046\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<h3><span id=\"-forEach-2\"><strong>\uff12-\uff13\uff0eforEach<\/strong><strong>\u30e1\u30bd\u30c3\u30c9\u306e\u7b2c\uff12\u5f15\u6570\u306b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u6e21\u3059\u4f8b<\/strong><\/span><\/h3>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u306f\u7b2c1\u5f15\u6570\u306e\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u4ed6\u306b\u3001\u7b2c2\u5f15\u6570\u3068\u3057\u3066\u4efb\u610f\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u6307\u5b9a\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u7b2c2\u5f15\u6570\u3068\u3057\u3066\u6307\u5b9a\u3057\u305f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306f\u3001\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u5185\u3067this\u306b\u3088\u308a\u547c\u3073\u51fa\u3057\u3066\u4f7f\u7528\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const fruits = [\u2018Apple\u2019, \u2018Banana\u2019, \u2018Cherry\u2019];\r\n\r\nconst fruitsPrice = {\r\n     \u2018Apple\u2019: 100,\r\n     \u2018Banana\u2019: 120,\r\n     \u2018Cherry\u2019: 80,\r\n     \u2018Orange\u2019: 90,\r\n     \u2018Lemon\u2019: 110,\r\n};\r\n\r\nfruits.forEach(function(fruit){\r\n     console.log(`${fruit}\u306e\u5024\u6bb5\u306f${this[fruit]\u5186\u3067\u3059\u3002}`);\r\n}, fruitsPrice);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ Apple\u306e\u5024\u6bb5\u306f100\u5186\u3067\u3059\u3002\r\n\/\/ Banana\u306e\u5024\u6bb5\u306f120\u5186\u3067\u3059\u3002\r\n\/\/ Cherry\u306e\u5024\u6bb5\u306f80\u5186\u3067\u3059\u3002\r\n<\/pre>\n<p>\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u5185\u306ethis\u306ffruitsPrice\u3092\u8868\u3057\u3066\u3044\u308b\u305f\u3081\u3001\u914d\u5217fruits\u306e\u8981\u7d20\u3092\u30ad\u30fc\u3068\u3057\u3066fruitsPrice\u306e100\u3084120\u3068\u3044\u3063\u305f\u5024\u3092\u53d6\u308a\u51fa\u3059\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<h2><span id=\"JavaScript_forEach-2\"><strong>\uff13\uff0eJavaScript forEach<\/strong><strong>\u30e1\u30bd\u30c3\u30c9\u306e\u6ce8\u610f\u70b9<\/strong><\/span><\/h2>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u306f\u914d\u5217\u3092\u51e6\u7406\u3059\u308b\u969b\u306b\u4fbf\u5229\u306a\u4e00\u65b9\u3067\u3001\u3044\u304f\u3064\u304b\u6ce8\u610f\u70b9\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<h3><span id=\"-continuebreak\"><strong>\uff13-\uff11\uff0e<\/strong><strong>continue<\/strong><strong>\u306b\u3088\u308b\u51e6\u7406\u306e\u4e2d\u65ad\u3084<\/strong><strong>break<\/strong><strong>\u306b\u3088\u308b\u629c\u3051\u51fa\u3057\u304c\u3067\u304d\u306a\u3044<\/strong><\/span><\/h3>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u3067\u306f\u3001continue\u3067\u51e6\u7406\u3092\u4e2d\u65ad\u3055\u305b\u305f\u308a\u3001break\u3067\u51e6\u7406\u81ea\u4f53\u3092\u629c\u3051\u51fa\u3057\u305f\u308a\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u305b\u3093\u3002forEach\u30e1\u30bd\u30c3\u30c9\u5185\u3067continue\u3084break\u3092\u8a18\u8ff0\u3059\u308b\u3068\u30a8\u30e9\u30fc\u3068\u306a\u3063\u3066\u3057\u307e\u3044\u307e\u3059\u3002\u305d\u3053\u3067\u3001continue\u3084break\u306e\u4ee3\u66ff\u6848\u3068\u3057\u3066\u540c\u3058\u51e6\u7406\u3092\u884c\u306a\u3046\u65b9\u6cd5\u3092\u3054\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n<h4><strong>\uff13-\uff11-\uff11\uff0e<\/strong><strong>\u51e6\u7406\u3092\u4e2d\u65ad\u3055\u305b\u305f\u3044\u5834\u5408\u306f<\/strong><strong>return<\/strong><strong>\u3067\u4ee3\u7528<\/strong><\/h4>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u3067\u51e6\u7406\u3092\u4e2d\u65ad\u3057\u3066\u6b21\u306e\u30eb\u30fc\u30d7\u51e6\u7406\u3092\u5b9f\u884c\u3055\u305b\u308b\u305f\u3081\u306b\u306freturn\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];\r\n\r\n\/\/ \u5076\u6570\u306e\u307f\u3092\u51fa\u529b\r\nnumbers.forEach(function(number){\r\n     if(number % 2 !== 0){\r\n          return;\r\n     }\r\n     console.log(number);\r\n});\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ 0\r\n\/\/ 2\r\n\/\/ 4\r\n\/\/ 6\r\n\/\/ 8\r\n<\/pre>\n<p>return\u3092\u7528\u3044\u308b\u3053\u3068\u3067\u305d\u306e\u6642\u70b9\u3067number\u304c\u5947\u6570\u306e\u6642\u306f\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u304c\u7d42\u4e86\u3055\u308c\u3001number\u3092\u51fa\u529b\u3059\u308b\u3053\u3068\u306a\u304f\u6b21\u306e\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u304c\u547c\u3073\u51fa\u3055\u308c\u307e\u3059\u3002\u3088\u3063\u3066\u3001continue\u3068\u540c\u3058\u6319\u52d5\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n<h4><strong>\uff13-\uff11-\uff12\uff0e<\/strong><strong>\u51e6\u7406\u81ea\u4f53\u3092\u629c\u3051\u51fa\u3057\u305f\u3044\u5834\u5408\u306f<\/strong><strong>for<\/strong><strong>\u6587\u3084<\/strong><strong>some<\/strong><strong>\u30e1\u30bd\u30c3\u30c9\u3067\u4ee3\u7528<\/strong><\/h4>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u3067\u51e6\u7406\u81ea\u4f53\u306e\u629c\u3051\u51fa\u3057\u306f\u3067\u304d\u306a\u3044\u305f\u3081\u3001for\u6587\u3084some\u30e1\u30bd\u30c3\u30c9\u3067\u4ee3\u7528\u3057\u307e\u3059\u3002for\u6587\u3092\u7528\u3044\u305f\u4f8b\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];\r\n\r\n\/\/ 3\u307e\u3067\u3092\u51fa\u529b\u30574\u4ee5\u964d\u306f\u51fa\u529b\u3055\u305b\u306a\u3044\r\nfor(var i = 0; i &lt; numbers.length; i++){\r\n     if(numbers[i] === 4){\r\n          break;\r\n     }\r\n     console.log(numbers[i]);\r\n}\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ 0\r\n\/\/ 1\r\n\/\/ 2\r\n\/\/ 3<\/pre>\n<p>\u307e\u305fsome\u30e1\u30bd\u30c3\u30c9\u3067\u4ee3\u7528\u3059\u308b\u3068\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u8a18\u8ff0\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];\r\n\r\n\/\/ 3\u307e\u3067\u3092\u51fa\u529b\u30574\u4ee5\u964d\u306f\u51fa\u529b\u3055\u305b\u306a\u3044\r\nnumbers.some(function(number){\r\n     if(number === 4){\r\n          return true;\r\n     }\r\n     console.log(number);\r\n});\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ 0\r\n\/\/ 1\r\n\/\/ 2\r\n\/\/ 3\r\n<\/pre>\n<p>some\u30e1\u30bd\u30c3\u30c9\u306f\u3001\u914d\u5217\u306e\u8981\u7d20\u306e\u3046\u3061\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306b\u6307\u5b9a\u3057\u305f\u6761\u4ef6\u30921\u8981\u7d20\u3067\u3082\u6e80\u305f\u3059\u5834\u5408\u306ftrue\u3092\u8fd4\u3057\u3066\u3001\u5168\u3066\u306e\u8981\u7d20\u304c\u6761\u4ef6\u3092\u6e80\u305f\u3055\u306a\u3044\u5834\u5408\u306e\u307ffalse\u3092\u8fd4\u3057\u307e\u3059\u3002\u3064\u307e\u308a\u3001\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u6761\u4ef6\u3092\u6e80\u305f\u3059\u8981\u7d20\u304c\u73fe\u308c\u305f\u6642\u70b9\u3067true\u3092\u8fd4\u3057\u3066\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306e\u547c\u3073\u51fa\u3057\u81ea\u4f53\u3092\u7d42\u4e86\u3059\u308b\u6027\u8cea\u304c\u3042\u308b\u305f\u3081\u3001\u629c\u3051\u51fa\u3057\u305f\u3044\u6761\u4ef6\u3092\u6307\u5b9a\u3059\u308b\u969b\u306btrue\u3092\u8fd4\u3057\u3066\u3042\u3052\u308b\u3053\u3068\u3067\u3001\u914d\u5217\u306e\u30eb\u30fc\u30d7\u51e6\u7406\u3092\u629c\u3051\u51fa\u3059\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n<h3><span id=\"i-4\"><strong>\uff13-\uff12\uff0e<\/strong><strong>\u4ed6\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u7528\u3044\u308b\u65b9\u304c\u9069\u5207\u306a\u5834\u9762\u304c\u3042\u308b<\/strong><\/span><\/h3>\n<p>\u914d\u5217\u306b\u5bfe\u3057\u3066\u7279\u5b9a\u306e\u51e6\u7406\u3092\u884c\u3044\u305f\u3044\u5834\u5408\u306f\u305d\u306e\u51e6\u7406\u306b\u9069\u3057\u305f\u30e1\u30bd\u30c3\u30c9\u304c\u4ed6\u306b\u5b58\u5728\u3059\u308b\u305f\u3081\u3001forEach\u30e1\u30bd\u30c3\u30c9\u3067\u306f\u306a\u3044\u65b9\u304c\u9069\u5207\u306b\u8a18\u8ff0\u3067\u304d\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u305d\u306e\u4e00\u4f8b\u3092\u3054\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n<h4><strong>\uff13-\uff12-\uff11\uff0e<\/strong><strong>\u914d\u5217\u304b\u3089\u7279\u5b9a\u306e\u8981\u7d20\u306e\u307f\u3092\u53d6\u308a\u51fa\u3059\u5834\u5408\u306f<\/strong><strong>find<\/strong><strong>\u30e1\u30bd\u30c3\u30c9<\/strong><strong>\u3084<\/strong><strong>filter<\/strong><strong>\u30e1\u30bd\u30c3\u30c9<\/strong><\/h4>\n<p>\u914d\u5217\u306e\u4e2d\u304b\u3089\u7279\u5b9a\u306e\u8981\u7d20\u3092\u53d6\u308a\u51fa\u3057\u305f\u3044\u5834\u5408\u306b\u306f\u3001find\u30e1\u30bd\u30c3\u30c9\u3084filter\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3046\u3068\u826f\u3044\u3067\u3059\u3002find\u30e1\u30bd\u30c3\u30c9\u306f\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306b\u6307\u5b9a\u3057\u305f\u6761\u4ef6\u306b\u5408\u81f4\u3059\u308b\u6700\u521d\u306e\u8981\u7d20\uff11\u3064\u3092\u53d6\u308a\u51fa\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];\r\n\r\nvar findNumber = numbers.find(function(number){\r\n     return number === 3;\r\n});\r\n\r\nconsole.log(findNumber);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ 3\r\n\r\n\/\/ \u30a2\u30ed\u30fc\u95a2\u6570\u3092\u4f7f\u3046\u3068\u3055\u3089\u306b\u30b9\u30c3\u30ad\u30ea\u8a18\u8ff0\u3067\u304d\u308b\r\nfindNumber = numbers.find((number) =&gt; number === 5);\r\n\r\nconsole.log(findNumber);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ 5\r\n<\/pre>\n<p>filter\u30e1\u30bd\u30c3\u30c9\u306f\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u306b\u6307\u5b9a\u3057\u305f\u6761\u4ef6\u306b\u5408\u81f4\u3059\u308b\u5168\u3066\u306e\u8981\u7d20\u3092\u914d\u5217\u3068\u3057\u3066\u8fd4\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];\r\n\r\nvar findNumbers = numbers.filter(function(number){\r\n     return number % 2 === 0 ;\r\n});\r\n\r\nconsole.log(findNumbers);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ [0, 2, 4, 6, 8]\r\n\r\n\/\/ \u30a2\u30ed\u30fc\u95a2\u6570\u3092\u4f7f\u3046\u3068\u3055\u3089\u306b\u30b9\u30c3\u30ad\u30ea\u8a18\u8ff0\u3067\u304d\u308b\r\nfindNumbers = numbers.filter((number) =&gt; number % 2 !== 0);\r\n\r\nconsole.log(findNumbers);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ [1, 3, 5, 7, 9]\r\n<\/pre>\n<h4><strong>\uff13-\uff12-\uff12\uff0e<\/strong><strong>\u914d\u5217\u3092\u52a0\u5de5\u3057\u3066\u5225\u306e\u914d\u5217\u3092\u4f5c\u308b\u5834\u5408\u306f<\/strong><strong>map<\/strong><strong>\u30e1\u30bd\u30c3\u30c9<\/strong><\/h4>\n<p>\u914d\u5217\u306e\u5404\u8981\u7d20\u3092\u52a0\u5de5\u3057\u3066\u5225\u306e\u914d\u5217\u3092\u4f5c\u308a\u305f\u3044\u5834\u5408\u306fmap\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3046\u3068\u826f\u3044\u3067\u3059\u3002map\u30e1\u30bd\u30c3\u30c9\u306f\u914d\u5217\u306e\u5404\u8981\u7d20\u306b\u5bfe\u3057\u3066\u30b3\u30fc\u30eb\u30d0\u30c3\u30af\u95a2\u6570\u3067\u51e6\u7406\u3092\u884c\u3044\u3001\u305d\u306e\u7d50\u679c\u3092\u65b0\u3057\u3044\u914d\u5217\u3068\u3057\u3066\u8fd4\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\">const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];\r\n\r\nconst doubledNumbers = numbers.map(function(number){\r\n     return number * 2 ;\r\n});\r\n\r\nconsole.log(doubledNumbers);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ [0, 2, 4, 6, 8, 10, 12, 14, 16, 18]\r\n\r\n\/\/ \u30a2\u30ed\u30fc\u95a2\u6570\u3092\u4f7f\u3046\u3068\u3055\u3089\u306b\u30b9\u30c3\u30ad\u30ea\u8a18\u8ff0\u3067\u304d\u308b\r\nconst squareNumbers = numbers.map((number) =&gt; number ** 2);\r\n\r\nconsole.log(squareNumbers);\r\n\r\n\/\/ \u2193\u51fa\u529b\u7d50\u679c\r\n\/\/ [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]<\/pre>\n<h2><span id=\"i-5\">\uff14\uff0e\u6700\u5f8c\u306b<\/span><\/h2>\n<p>forEach\u30e1\u30bd\u30c3\u30c9\u306f\u914d\u5217\u306e\u7e70\u308a\u8fd4\u3057\u51e6\u7406\u3092\u884c\u306a\u3046\u969b\u306b\u4fbf\u5229\u306a\u30e1\u30bd\u30c3\u30c9\u3067\u3059\u3002\u4eca\u56de\u3054\u7d39\u4ecb\u3057\u305f\u3088\u3046\u306b\u69d8\u3005\u306a\u4f7f\u3044\u65b9\u304c\u3067\u304d\u308b\u6c4e\u7528\u7684\u306a\u30e1\u30bd\u30c3\u30c9\u3067\u3059\u304c\u3001\u6ce8\u610f\u70b9\u3082\u8e0f\u307e\u3048\u3066\u4f7f\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<pre class=\"prettyprint lang:default decode:true\"><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>JavaScript\u3067\u914d\u5217\u306e\uff11\u3064\uff11\u3064\u306e\u8981\u7d20\u3092\u30eb\u30fc\u30d7\u51e6\u7406\u3067\u9806\u306b\u53d6\u308a\u51fa\u3057\u3066\u51e6\u7406\u3092\u884c\u306a\u3046\u6642\u306b\u7528\u3044\u3089\u308c\u308b\u30e1\u30bd\u30c3\u30c9\u306e\uff11\u3064\u3068\u3057\u3066\u3001forEach\u30e1\u30bd\u30c3\u30c9\u304c\u3042\u308a\u307e\u3059\u3002 \u901a\u5e38\u30eb\u30fc\u30d7\u51e6\u7406\u3092\u884c\u306a\u3046\u6642\u306ffor\u6587\u304c\u7528\u3044\u3089\u308c\u308b\u3053\u3068\u304c\u591a\u3044\u304b\u3068\u601d\u3044\u307e [&hellip;]<\/p>\n","protected":false},"author":25,"featured_media":4310,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[27],"acf":[],"_links":{"self":[{"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/posts\/4269"}],"collection":[{"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/users\/25"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/comments?post=4269"}],"version-history":[{"count":6,"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/posts\/4269\/revisions"}],"predecessor-version":[{"id":6242,"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/posts\/4269\/revisions\/6242"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/media\/4310"}],"wp:attachment":[{"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/media?parent=4269"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bold.ne.jp\/engineer-club\/wp-json\/wp\/v2\/categories?post=4269"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}