{"id":10142,"date":"2025-12-26T16:42:26","date_gmt":"2025-12-26T07:42:26","guid":{"rendered":"https:\/\/techmania.jp\/blog\/?p=10142"},"modified":"2025-12-26T16:42:28","modified_gmt":"2025-12-26T07:42:28","slug":"javascript-switch","status":"publish","type":"post","link":"https:\/\/techmania.jp\/blog\/javascript-switch\/","title":{"rendered":"\u3010JavaScript\u5165\u9580\u3011switch\u6587\u3067\u8907\u6570\u306e\u6761\u4ef6\u3092\u308f\u304b\u308a\u3084\u3059\u304f\u5206\u5c90\u3059\u308b"},"content":{"rendered":"\n

JavaScript\u3067\u6761\u4ef6\u5206\u3051\u3092\u884c\u3046\u969b\u306b\u4f7f\u7528\u3055\u308c\u308b\u69cb\u6587\u3068\u3057\u3066\u3001if\u6587\u306e\u4ed6\u306b\u3082\u3046\uff11\u3064switch\u6587\u3068\u547c\u3070\u308c\u308b\u69cb\u6587\u304c\u3042\u308a\u307e\u3059\u3002
\u6bd4\u8f03\u3059\u308b\u6761\u4ef6\u3088\u3063\u3066\u306fif\u6587\u3088\u308a\u3082 switch\u6587\u306e\u65b9\u304c\u53ef\u8aad\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u3092\u66f8\u3051\u308b\u5834\u5408\u304c\u3042\u308b\u305f\u3081\u3001\u3069\u3061\u3089\u306e\u4f7f\u3044\u65b9\u3082\u7406\u89e3\u3057\u3066\u304a\u304f\u3053\u3068\u304c\u91cd\u8981\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n

\u305d\u3053\u3067\u4eca\u56de\u306f\u3001JavaScript\u3067 switch\u6587\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5\u306b\u3064\u3044\u3066\u89e3\u8aac\u3057\u3066\u3044\u304d\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002
\u57fa\u672c\u69cb\u6587\u3084\u7c21\u5358\u306a\u5fdc\u7528\u65b9\u6cd5\u3001if\u6587\u3068\u306e\u4f7f\u3044\u5206\u3051\u306e\u57fa\u6e96\u306a\u3069\u306b\u3064\u3044\u3066\u3082\u5408\u308f\u305b\u3066\u89e3\u8aac\u3057\u3066\u3044\u304d\u307e\u3059\u306e\u3067\u3001\u305c\u3072\u53c2\u8003\u306b\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n

JavaScript\u306eswitch\u6587\u3068\u306f\uff1f<\/h2>\n\n\n\n

switch\u6587\u3068\u306f\u3001\u6761\u4ef6\u5206\u5c90\u3092\u884c\u3046\u969b\u306b\u4f7f\u7528\u3059\u308b\u69cb\u6587\u306e\u4e00\u7a2e\u3067\u3059\u3002
\u540c\u3058\u304f\u6761\u4ef6\u5206\u5c90\u3067\u4f7f\u7528\u3059\u308b if\u6587\u3068\u540c\u69d8\u306b\u3001\u6307\u5b9a\u3057\u305f\u6761\u4ef6\u306b\u5fdc\u3058\u3066\u5b9f\u884c\u3059\u308b\u51e6\u7406\u3092\u8a18\u8ff0\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n

switch\u6587\u306f\u3001\u7279\u5b9a\u306e\u5024\u306b\u4e00\u81f4\u3059\u308b\u6761\u4ef6\u304c\u3042\u308b\u304b\u3092\u6bd4\u8f03\u3057\u305f\u3044\u3001\u304b\u3064\u6bd4\u8f03\u6761\u4ef6\u304c\u591a\u6570\u306b\u6e21\u308b\u5834\u5408\u306b\u4fbf\u5229\u306a\u69cb\u6587\u3067\u3059\u3002<\/p>\n\n\n\n

switch\u306e\u4f7f\u3044\u65b9<\/h2>\n\n\n\n

\u305d\u308c\u3067\u306f\u3055\u3063\u305d\u304f\u3001switch\u6587\u306e\u8a73\u3057\u3044\u4f7f\u3044\u65b9\u306b\u3064\u3044\u3066\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n

\u57fa\u672c\u69cb\u6587<\/h3>\n\n\n\n

switch\u6587\u3092\u4f7f\u7528\u3059\u308b\u969b\u306e\u57fa\u672c\u69cb\u6587\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u8a18\u8ff0\u3057\u307e\u3059\u3002<\/p>\n\n\n\n

\u3010\u57fa\u672c\u69cb\u6587\u3011<\/strong><\/p>\n\n\n\n

switch (\u6bd4\u8f03\u5bfe\u8c61\u306e\u5024) {\n\n  case \u6761\u4ef6\uff11:\n    \/\/ \u5b9f\u884c\u3059\u308b\u51e6\u7406\n    break;\n\n  case \u6761\u4ef62:\n    \/\/ \u5b9f\u884c\u3059\u308b\u51e6\u7406\n    break;\n  .\n  .\n  .\n}<\/code><\/pre><\/div>\n\n\n\n
switch\u6587\u306b\u304a\u3051\u308b\u6bd4\u8f03\u6761\u4ef6\u306f\u3001\u53b3\u5bc6\u7b49\u4fa1\u6f14\u7b97\u5b50(===) \u3067\u306e\u6bd4\u8f03\u306e\u307f\u3068\u306a\u308a\u307e\u3059\u3002
\u305d\u306e\u4ee3\u308f\u308a\u306b\u3001\u6761\u4ef6\u5f0f\u3092\u7701\u7565\u3057\u3066\u6bd4\u8f03\u3059\u308b\u5024\u306e\u307f\u3092\u8a18\u8ff0\u3059\u308b\u306e\u304c\u7279\u5fb4\u3067\u3059\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
const num = 3;\n\nswitch (num) {\n  case 1:\n    console.log("case 1 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n  case 2:\n    console.log("case 2 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n  case 3:\n    console.log("case 3 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n}<\/code><\/pre><\/div>\n\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n\n
case 3 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f<\/code><\/pre><\/div>\n\n\n\n
\u307e\u305f\u3001switch\u6587\u306e\u5834\u5408\u306f\u4e0a\u8ff0\u306e\u3088\u3046\u306b\u3001\u5404case\u306e\u51e6\u7406\u306e\u7d42\u308f\u308a\u306b break\u3092\u8a18\u8ff0\u3057\u307e\u3059\u3002<\/p>\n\n\n\n
break\u3092\u5165\u308c\u306a\u3044\u3068\u3069\u3046\u306a\u308b\uff1f<\/h3>\n\n\n\n
\u57fa\u672c\u7684\u306b\u306f\u3001\u51e6\u7406\u306e\u7d42\u308f\u308a\u306b\u5fc5\u305a\u8a18\u8ff0\u3059\u308b break\u3067\u3059\u304c\u3001\u4ed5\u69d8\u4e0a\u306f\u7701\u7565\u3059\u308b\u3053\u3068\u3082\u53ef\u80fd\u3067\u3059\u3002
\u305d\u306e\u5834\u5408\u306f\u4e00\u4f53\u3069\u306e\u3088\u3046\u306a\u6319\u52d5\u3092\u3059\u308b\u306e\u3067\u3057\u3087\u3046\u304b\uff1f<\/p>\n\n\n\n
\u4ee5\u4e0b\u306e\u4f8b\u3067\u3001\u5b9f\u969b\u306e\u52d5\u304d\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
const num = 2;\n\nswitch (num) {\n  case 1:\n    console.log("case 1 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n  case 2:\n    console.log("case 2 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n  case 3:\n    console.log("case 3 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n}<\/code><\/pre><\/div>\n\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n\n
case 2 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f\ncase 3 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f<\/code><\/pre><\/div>\n\n\n\n
\u5024\u304c\u4e00\u81f4\u3059\u308b\u306e\u306f case2\u306e\u6761\u4ef6\u3067\u3059\u304c\u3001\u5b9f\u884c\u7d50\u679c\u3092\u898b\u308b\u3068\u3001\u305d\u306e\u4e0b\u306b\u3042\u308b case3\u306e\u51e6\u7406\u307e\u3067\u5b9f\u884c\u3055\u308c\u3066\u3044\u308b\u306e\u304c\u5206\u304b\u308b\u304b\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\u3053\u306e\u3088\u3046\u306b\u3001break\u306e\u8a18\u8ff0\u3092\u7701\u7565\u3057\u305f\u5834\u5408\u3001\u4e00\u81f4\u3057\u305f\u6761\u4ef6\u306e\u51e6\u7406\u304c\u5b9f\u884c\u3055\u308c\u3066\u3082 switch\u6587\u304b\u3089\u629c\u3051\u51fa\u3055\u305a\u306b\u3001break\u304c\u8a18\u8ff0\u3055\u308c\u3066\u3044\u308b\u884c\u306b\u5f53\u305f\u308b\u307e\u3067\u5404\u6761\u4ef6\u306e\u51e6\u7406\u304c\u5b9f\u884c\u3055\u308c\u7d9a\u3051\u307e\u3059\u3002
\u3053\u306e\u6027\u8cea\u3092\u5229\u7528\u3057\u3066\u3001\u308f\u3056\u3068 break\u3092\u8a18\u8ff0\u305b\u305a\u306b\u8907\u6570\u306e\u51e6\u7406\u3092\u7d9a\u3051\u3066\u5b9f\u884c\u3059\u308b\u65b9\u6cd5\u3082\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n
if \u2026 else if\u6587\u3068\u306e\u4f7f\u3044\u5206\u3051<\/h2>\n\n\n\n
JavaScript\u3067\u3001\u540c\u3058\u304f\u6761\u4ef6\u5206\u3051\u306e\u969b\u306b\u4f7f\u7528\u3055\u308c\u308b\u69cb\u6587\u306e\uff11\u3064\u306b\u3001if\u6587\u304c\u3042\u308a\u307e\u3059\u3002
\u3053\u306e if\u6587\u306e\u4e2d\u3067\u3082\u3001if \u2026 else if\u6587\u3068\u547c\u3070\u308c\u308b\u69cb\u6587\u3092\u4f7f\u3063\u3066\u3001switch\u6587\u3068\u540c\u3058\u6319\u52d5\u3092\u5b9f\u88c5\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n
\u3053\u3053\u304b\u3089\u306f\u3001if \u2026 else if\u6587\u306e\u4f7f\u3044\u65b9\u3084\u3001switch\u6587\u3068\u306e\u4f7f\u3044\u5206\u3051\u65b9\u306b\u3064\u3044\u3066\u89e3\u8aac\u3057\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
if \u2026 else if\u6587\u306e\u57fa\u672c\u69cb\u6587<\/h3>\n\n\n\n
if \u2026 else if\u6587\u3092\u4f7f\u7528\u3059\u308b\u969b\u306e\u57fa\u672c\u69cb\u6587\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u8a18\u8ff0\u3057\u307e\u3059\u3002<\/p>\n\n\n\n
\u3010\u57fa\u672c\u69cb\u6587\u3011<\/strong><\/p>\n\n\n\n
if (\u6761\u4ef6\u5f0f1) {\n\t\/\/\u5b9f\u884c\u3059\u308b\u51e6\u7406\u5185\u5bb9\n} else if (\u6761\u4ef6\u5f0f2) {\n\t\/\/\u5b9f\u884c\u3059\u308b\u51e6\u7406\u5185\u5bb9\n}<\/code><\/pre><\/div>\n\n\n\n
if \u2026 else if\u6587\u306f\u3001\u5206\u5c90\u3057\u305f\u3044\u6761\u4ef6\u306e\u6570\u3060\u3051 else if \u3092\u7e4b\u3052\u3066\u8a18\u8ff0\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u305f\u3081\u3001switch\u6587\u3068\u540c\u69d8\u306b\u8907\u6570\u306e\u30b1\u30fc\u30b9\u306b\u5bfe\u5fdc\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002
\u6761\u4ef6\u5f0f\u306e\u8a18\u8ff0\u65b9\u6cd5\u306f\u3001if\u6587\u3068\u540c\u69d8\u3067\u3059\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
const num = 7;\nif (num < 5) {\n\tconsole.log("5\u3088\u308a\u5c0f\u3055\u3044\u6570\u5024\u3067\u3059");\n} else if (num === 5) {\n\tconsole.log("5\u3067\u3059");\n} else if (num > 5) {\n\tconsole.log("5\u3088\u308a\u5927\u304d\u3044\u6570\u5024\u3067\u3059");\n}<\/code><\/pre><\/div>\n\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n\n
5\u3088\u308a\u5927\u304d\u3044\u6570\u5024\u3067\u3059<\/code><\/pre><\/div>\n\n\n\n
switch\u6587\u306e\u6761\u4ef6\u5f0f\u306f\u3001\u4e0a\u8a18\u306e\u30b3\u30fc\u30c9\u306e\u3046\u3061 \u300cnum === 5\u300d \u3068\u540c\u3058\u6bd4\u8f03\u5f0f\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n
switch\u3068if\u2026else if\u6587\u306e\u4f7f\u3044\u5206\u3051<\/h3>\n\n\n\n
\u4e0a\u8ff0\u3057\u305f\u3088\u3046\u306b\u3001switch\u6587\u3068 if\u2026else if\u6587\u306f\u3069\u3061\u3089\u3082\u540c\u3058\u3088\u3046\u306a\u6319\u52d5\u3092\u3057\u307e\u3059\u3002
\u3067\u306f\u3001\u3069\u306e\u3088\u3046\u306b\u4f7f\u3044\u5206\u3051\u3092\u3059\u308c\u3070\u3044\u3044\u306e\u3067\u3057\u3087\u3046\u304b\uff1f<\/p>\n\n\n\n
if\u2026else if\u6587\u306f\u3001\u6bd4\u8f03\u6f14\u7b97\u5b50\u3092\u4f7f\u7528\u3057\u3066\u69d8\u3005\u306a\u6761\u4ef6\u5f0f\u3092\u6307\u5b9a\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002
\u4f8b\u3048\u3070\u3001\u4e00\u5b9a\u306e\u6570\u5024\u3088\u308a\u3082\u5927\u304d\u3044\u5834\u5408\u3001\u3042\u308b\u3044\u306f\u5c0f\u3055\u3044\u5834\u5408\u3001\u5168\u304f\u540c\u3058\u5024\u3067\u3042\u308b\u5834\u5408\u306a\u3069\u3001\u4f7f\u7528\u3059\u308b\u6f14\u7b97\u5b50\u306b\u3088\u3063\u3066\u67d4\u8edf\u306b\u5909\u66f4\u53ef\u80fd\u3067\u3059\u3002<\/p>\n\n\n\n
\u4e00\u65b9\u3001switch\u6587\u306e\u5834\u5408\u306f\u65e2\u306b\u4e0a\u8ff0\u3057\u305f\u3088\u3046\u306b\u3001\u53b3\u5bc6\u7b49\u4fa1\u6f14\u7b97\u5b50(===) \u3067\u306e\u6bd4\u8f03\u306e\u307f\u3068\u306a\u308a\u307e\u3059\u3002
\u305d\u306e\u4ee3\u308f\u308a\u306b\u6761\u4ef6\u5f0f\u306e\u8a18\u8ff0\u3092\u7701\u7565\u3067\u304d\u308b\u305f\u3081\u3001\u3069\u306e\u5024\u3068\u6bd4\u8f03\u3059\u308b\u304b\u304c if\u2026else if\u6587\u3088\u308a\u3082\u8996\u899a\u7684\u306b\u7406\u89e3\u3057\u3084\u3059\u3044\u50be\u5411\u306b\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n
\u540c\u3058\u5185\u5bb9\u306e\u51e6\u7406\u3092\u3001switch\u6587\u3068 if\u2026else if\u6587\u3067\u898b\u6bd4\u3079\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
\/\/ switch\u6587\u306e\u5834\u5408\nconst str = "\u30b0\u30fc";\nswitch(str) {\n  case "\u30b0\u30fc":\n    console.log("\u30b0\u30fc\u3092\u51fa\u3057\u307e\u3057\u305f");\n    break;\n  case "\u30c1\u30e7\u30ad":\n    console.log("\u30c1\u30e7\u30ad\u3092\u51fa\u3057\u307e\u3057\u305f");\n    break;\n  case "\u30d1\u30fc":\n    console.log("\u30d1\u30fc\u3092\u51fa\u3057\u307e\u3057\u305f");\n    break;\n}\n\n\/\/ if\u2026else if\u6587\u306e\u5834\u5408\nconst str = "\u30b0\u30fc";\nif(str === "\u30b0\u30fc") {\n    console.log("\u30b0\u30fc\u3092\u51fa\u3057\u307e\u3057\u305f");\n} else if(str === "\u30c1\u30e7\u30ad") {\n    console.log("\u30c1\u30e7\u30ad\u3092\u51fa\u3057\u307e\u3057\u305f");\n} else if(str === "\u30d1\u30fc") {\n    console.log("\u30c1\u30e7\u30ad\u3092\u51fa\u3057\u307e\u3057\u305f");   \n}<\/code><\/pre><\/div>\n\n\n\n
switch\u6587\u306f\u6bd4\u8f03\u6761\u4ef6\u304c1\u3064\u306b\u7d5e\u3089\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u8a18\u8ff0\u3055\u308c\u3066\u3044\u308b\u5024\u3092\u898b\u308b\u3060\u3051\u3067\u6bd4\u8f03\u5bfe\u8c61\u3092\u77ac\u6642\u306b\u7406\u89e3\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n
\u4e00\u65b9\u3001if\u2026else if\u6587\u306f\u6bd4\u8f03\u3059\u308b\u5024\u3060\u3051\u3067\u306a\u304f\u3001\u3069\u306e\u6f14\u7b97\u5b50\u304c\u4f7f\u7528\u3055\u308c\u3066\u3044\u308b\u304b\u307e\u3067\u78ba\u8a8d\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u305f\u3081\u3001switch\u6587\u3088\u308a\u3082\u76f4\u611f\u7684\u306a\u7406\u89e3\u304c\u96e3\u3057\u304f\u306a\u308a\u304c\u3061\u3067\u3059\u3002
\u305d\u306e\u4ee3\u308f\u308a\u306b\u3001switch\u6587\u3067\u306f\u6307\u5b9a\u3067\u304d\u306a\u3044\u6bd4\u8f03\u6761\u4ef6\u3082\u67d4\u8edf\u306b\u7e54\u308a\u4ea4\u305c\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n
2\u3064\u306e\u69cb\u6587\u3092\u4f7f\u3044\u5206\u3051\u308b\u969b\u306f\u3001\u5168\u3066\u306e\u5024\u3092 === \u3067\u6bd4\u8f03\u3059\u308b\u304b\u3069\u3046\u304b\u3092\u57fa\u6e96\u306b\u3059\u308b\u3068\u3044\u3044\u3067\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
default\u30ad\u30fc\u30ef\u30fc\u30c9\u306e\u4f7f\u3044\u65b9<\/h2>\n\n\n\n
switch\u6587\u3067\u306f\u3001\u3044\u305a\u308c\u306e\u6761\u4ef6\u306b\u3082\u4e00\u81f4\u3057\u306a\u304b\u3063\u305f\u5834\u5408\u306e\u51e6\u7406\u3092\u8a18\u8ff0\u3059\u308b\u65b9\u6cd5\u3068\u3057\u3066\u3001default \u304c\u7528\u610f\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\u4ee5\u4e0b\u306e\u4f8b\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
const num = 5;\n\nswitch (num) {\n  case 1:\n    console.log("case 1 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n  case 2:\n    console.log("case 2 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n  case 3:\n    console.log("case 3 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n  default:\n    console.log("\u60f3\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044\u6570\u5024\u3067\u3059");\n    break;\n}<\/code><\/pre><\/div>\n\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n\n
\u60f3\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044\u6570\u5024\u3067\u3059<\/code><\/pre><\/div>\n\n\n\n
\u5909\u6570\u306b\u4ee3\u5165\u3055\u308c\u3066\u3044\u308b\u5024\u306f\u3001\u6307\u5b9a\u3055\u308c\u3066\u3044\u308b\u3044\u305a\u308c\u306e\u6761\u4ef6\u306b\u3082\u4e00\u81f4\u3057\u306a\u3044\u5024\u3067\u3059\u3002
\u305d\u306e\u305f\u3081\u3001default\u306b\u8a18\u8ff0\u3057\u305f\u51e6\u7406\u5185\u5bb9\u304c\u5b9f\u884c\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\u307e\u305f\u3001\u57fa\u672c\u7684\u306b\u306f switch\u6587\u306e\u7d42\u308f\u308a\u306b\u8a18\u8ff0\u3055\u308c\u308b\u3053\u3068\u304c\u591a\u3044\u3067\u3059\u304c\u3001\u8a18\u8ff0\u5834\u6240\u3092\u5909\u66f4\u3057\u3066\u3082\u52d5\u4f5c\u306b\u5f71\u97ff\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
const num = 3;\n\nswitch (num) {\n  case 1:\n    console.log("case 1 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n\n \/\/ \u9593\u306b\u8a18\u8ff0\u3057\u3066\u3082\u554f\u984c\u306a\u3044\n  default:\n    console.log("\u60f3\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044\u6570\u5024\u3067\u3059");\n    break;\n\n  case 2:\n    console.log("case 2 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n\n  case 3:\n    console.log("case 3 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f");\n    break;\n}<\/code><\/pre><\/div>\n\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n\n
case 3 \u306b\u4e00\u81f4\u3057\u307e\u3057\u305f<\/code><\/pre><\/div>\n\n\n\n
\u8907\u6570\u306e case \u3067\u540c\u3058\u51e6\u7406\u3092\u3059\u308b<\/h2>\n\n\n\n
break\u3092\u8a18\u8ff0\u3057\u306a\u304b\u3063\u305f\u5834\u5408\u306b\u3001switch\u6587\u3092\u629c\u3051\u305a\u306b\u51e6\u7406\u304c\u7d99\u7d9a\u3055\u308c\u308b\u6319\u52d5\u3092\u5229\u7528\u3057\u3066\u3001\u8907\u6570\u306e case\u3067\u540c\u3058\u51e6\u7406\u3092\u5b9f\u884c\u3055\u305b\u308b\u3053\u3068\u3082\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n
\u4ee5\u4e0b\u306e\u4f8b\u3067\u3001\u5b9f\u969b\u306e\u52d5\u4f5c\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
const num = 5;\n\nswitch (num) {\n  case 1:\n  case 2:\n  case 3:\n    console.log("1\u301c3\u306e\u3044\u305a\u308c\u304b\u3067\u3059");\n    break;\n\n  case 4:\n  case 5:\n  case 6:\n    console.log("4\u301c6\u306e\u3044\u305a\u308c\u304b\u3067\u3059");\n    break;\n\n  case 7:\n  case 8:\n  case 9:\n    console.log("7\u301c9\u306e\u3044\u305a\u308c\u304b\u3067\u3059");\n    break;\n\n  default:\n    console.log("10\u4ee5\u4e0a\u306e\u6570\u5024\u3067\u3059");\n    break;\n}<\/code><\/pre><\/div>\n\n\n\n
\u3010\u5b9f\u884c\u7d50\u679c\u3011<\/strong><\/p>\n\n\n\n
4\u301c6\u306e\u3044\u305a\u308c\u304b\u3067\u3059<\/code><\/pre><\/div>\n\n\n\n
\u540c\u4e00\u306e\u51e6\u7406\u3092\u884c\u3046 case \u306e\u3046\u3061\u3001\u4e00\u756a\u6700\u5f8c\u306e case \u306e\u307f\u51e6\u7406\u5185\u5bb9\u3068 break\u3092\u8a18\u8ff0\u3059\u308b\u3053\u3068\u3067\u3001\u8907\u6570\u306e\u6761\u4ef6\u306e\u51e6\u7406\u304c\u540c\u3058\u7b87\u6240\u306b\u5230\u9054\u3059\u308b\u3088\u3046\u306b\u3059\u308b\u4ed5\u7d44\u307f\u3067\u3059\u3002
\u3053\u306e\u3088\u3046\u306b\u3001\u72b6\u6cc1\u306b\u5fdc\u3058\u3066\u7279\u5b9a\u306e case \u306e\u51e6\u7406\u5185\u5bb9\u3092\uff11\u3064\u306b\u307e\u3068\u3081\u308b\u3053\u3068\u3082\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n
\u6761\u4ef6\u5f0f\u306b\u7528\u3044\u308b\u7b49\u4fa1\u6f14\u7b97\u5b50\u306e\u4f7f\u3044\u5206\u3051<\/h2>\n\n\n\n
switch\u6587\u306f\u3001\u53b3\u5bc6\u7b49\u4fa1\u6f14\u7b97\u5b50 (===) \u306b\u3088\u308b\u6bd4\u8f03\u304c\u884c\u308f\u308c\u308b\u3053\u3068\u306f\u65e2\u306b\u4e0a\u8ff0\u3057\u307e\u3057\u305f\u304c\u3001JavaScript\u306b\u306f\u7b49\u4fa1\u6f14\u7b97\u5b50 (==) \u3068\u3044\u3046\u6bd4\u8f03\u6f14\u7b97\u5b50\u3082\u5b58\u5728\u3057\u307e\u3059\u3002
\u4e00\u898b\u3059\u308b\u3068\u540c\u3058\u3088\u3046\u306b\u898b\u3048\u308b\u3053\u306e2\u3064\u306e\u6f14\u7b97\u5b50\u3067\u3059\u304c\u3001\u7279\u5b9a\u306e\u5834\u5408\u306b\u304a\u3044\u3066\u6319\u52d5\u304c\u7570\u306a\u308b\u305f\u3081\u3001\u9055\u3044\u3092\u7406\u89e3\u3057\u3066\u304a\u304f\u3053\u3068\u306f\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n
\u307e\u305a\u3001\u3069\u3061\u3089\u306e\u6f14\u7b97\u5b50\u3082\u3001\u6bd4\u8f03\u3059\u308b\u5024\u540c\u58eb\u304c\u540c\u4e00\u3067\u3042\u308b\u304b\u5426\u304b\u3092\u6bd4\u8f03\u3059\u308b\u6f14\u7b97\u5b50\u3067\u3059\u3002
\u4f8b\u3048\u3070\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30b1\u30fc\u30b9\u306f\u3069\u3061\u3089\u3082 true\u5224\u5b9a\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
console.log(1 == 1);   \/\/ true\nconsole.log(1 === 1);  \/\/ true<\/code><\/pre><\/div>\n\n\n\n
\u3053\u306e2\u3064\u306e\u6f14\u7b97\u5b50\u306e\u9055\u3044\u306f\u3001\u6bd4\u8f03\u3059\u308b\u5024\u306e\u578b\u304c\u7570\u306a\u308b\u5834\u5408\u306b\u3001\u9055\u3046\u5024\u3067\u3042\u308b\u3068\u898b\u306a\u3059\u304b\u3069\u3046\u304b\u3067\u3059\u3002
\u4ee5\u4e0b\u306e\u30b1\u30fc\u30b9\u306e\u5834\u5408\u3001\u7b49\u4fa1\u6f14\u7b97\u5b50\u3068\u53b3\u5bc6\u7b49\u4fa1\u6f14\u7b97\u5b50\u3067\u306f\u6bd4\u8f03\u7d50\u679c\u304c\u7570\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n
\u3010\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3011<\/strong><\/p>\n\n\n\n
console.log(1 == "1");   \/\/ true\nconsole.log(1 === "1");  \/\/ false<\/code><\/pre><\/div>\n\n\n\n
\u7b49\u4fa1\u6f14\u7b97\u5b50\u306e\u5834\u5408\u306f\u3001\u7570\u306a\u308b\u578b\u306e\u969b\u306b\u578b\u5909\u63db\u3092\u884c\u3063\u3066\u304b\u3089\u6bd4\u8f03\u3092\u3059\u308b\u305f\u3081\u3001\u540c\u4e00\u306e\u5024\u3067\u3042\u308b\u3068\u5224\u65ad\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\u307e\u3068\u3081<\/h2>\n\n\n\n
\u3044\u304b\u304c\u3067\u3057\u305f\u304b\uff1f\u4eca\u56de\u306f\u3001JavaScript\u3067 switch\u6587\u3092\u4f7f\u7528\u3059\u308b\u65b9\u6cd5\u306b\u3064\u3044\u3066\u89e3\u8aac\u3057\u307e\u3057\u305f\u3002<\/p>\n\n\n\n
break\u306e\u6709\u7121\u306b\u3088\u3063\u3066\u52d5\u4f5c\u304c\u7570\u306a\u3063\u305f\u308a\u3001\u6bd4\u8f03\u6761\u4ef6\u304c if\u6587\u3088\u308a\u3082\u9650\u3089\u308c\u3066\u3044\u305f\u308a\u3068\u3001switch\u6587\u306a\u3089\u3067\u306f\u306e\u30dd\u30a4\u30f3\u30c8\u304c\u3044\u304f\u3064\u304b\u3042\u3063\u305f\u304b\u3068\u601d\u3044\u307e\u3059\u3002
\u305d\u308c\u305e\u308c\u306e\u69cb\u6587\u3092\u4f7f\u3044\u5206\u3051\u3066\u3044\u304f\u4e0a\u3067\u3001\u52d5\u4f5c\u306e\u9055\u3044\u306f\u3057\u3063\u304b\u308a\u3068\u628a\u63e1\u3057\u3066\u304a\u304f\u3079\u304d\u30dd\u30a4\u30f3\u30c8\u3067\u3059\u306e\u3067\u3001\u3057\u3063\u304b\u308a\u3068\u304a\u3055\u3048\u3066\u304a\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n
\u305c\u3072\u3053\u306e\u8a18\u4e8b\u3082\u53c2\u8003\u306b\u3057\u306a\u304c\u3089\u3001switch\u6587\u306e\u4f7f\u3044\u65b9\u3092\u30de\u30b9\u30bf\u30fc\u3057\u3066\u3001\u4eca\u5f8c\u306e\u958b\u767a\u306b\u5f79\u7acb\u3066\u3066\u3044\u3063\u3066\u304f\u3060\u3055\u3044\u306d\uff01<\/p>\n\n\n\n
JavaScript\u306e\u52c9\u5f37\u65b9\u6cd5\u306f\uff1f<\/h2>\n\n\n
\u66f8\u7c4d\u3084\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u3067\u5b66\u7fd2\u3059\u308b\u65b9\u6cd5\u304c\u3042\u308a\u307e\u3059\u3002\u6628\u4eca\u3067\u306f\u3001YouTube\u306a\u3069\u306e\u52d5\u753b\u30b5\u30a4\u30c8\u3084\u30a8\u30f3\u30b8\u30cb\u30a2\u306e\u30b3\u30df\u30e5\u30cb\u30c6\u30a3\u30b5\u30a4\u30c8\u306a\u3069\u3082\u5145\u5b9f\u3057\u3066\u3044\u3066\u591a\u304f\u306e\u60c5\u5831\u304c\u624b\u306b\u5165\u308a\u307e\u3059\u3002
\u305d\u3057\u3066\u3001\u3088\u308a\u52b9\u7387\u7684\u306b\u77e5\u8b58\u30fb\u30b9\u30ad\u30eb\u3092\u7fd2\u5f97\u3059\u308b\u306b\u306f\u3001\u77e5\u8b58\u3092\u3064\u3051\u306a\u304c\u3089\u5b9f\u969b\u306b\u624b\u3092\u52d5\u304b\u3057\u3066\u307f\u308b\u306a\u3069\u3001\u30a4\u30f3\u30d7\u30c3\u30c8\u3068\u30a2\u30a6\u30c8\u30d7\u30c3\u30c8\u3092\u7e70\u308a\u8fd4\u3057\u3066\u3044\u304f\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u7279\u306b\u72ec\u5b66\u306e\u5834\u5408\u306f\u3001\u6709\u8b58\u8005\u306b\u8cea\u554f\u304c\u3067\u304d\u305f\u308a\u30d5\u30a3\u30fc\u30c9\u30d0\u30c3\u30af\u3092\u3082\u3089\u3048\u308b\u3088\u3046\u306a\u74b0\u5883\u304c\u3042\u308b\u3068\u3001\u7406\u89e3\u5ea6\u304c\u6df1\u307e\u308b\u3067\u3057\u3087\u3046\u3002<\/p>\n
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IT\u30b9\u30ad\u30eb\u9700\u8981\u306e\u9ad8\u307e\u308a\u3068\u3068\u3082\u306b\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30b9\u30af\u30fc\u30eb\u3082\u5897\u3048\u307e\u3057\u305f\u3002\u3057\u304b\u3057\u3001\u3069\u306e\u30b9\u30af\u30fc\u30eb\u306b\u901a\u3046\u3079\u304d\u304b\u8ff7\u3063\u3066\u3057\u307e\u3046\u4eba\u3082\u3044\u308b\u3067\u3057\u3087\u3046\u3002\u305d\u3093\u306a\u65b9\u306b\u306f\u30c6\u30c3\u30af\u30de\u30cb\u30a2\u3092\u304a\u3059\u3059\u3081\u3057\u307e\u3059\uff01\u3053\u308c\u307e\u3067\u591a\u304f\u306eIT\u30a8\u30f3\u30b8\u30cb\u30a2\u3092\u80b2\u6210\u30fb\u8f29\u51fa\u3057\u3066\u304d\u305f\u30c6\u30c3\u30af\u30de\u30cb\u30a2\u3067\u3082\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u30b9\u30af\u30fc\u30eb\u3092\u958b\u8b1b\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n
\n
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