{"id":4526,"date":"2025-01-13T14:37:36","date_gmt":"2025-01-13T05:37:36","guid":{"rendered":"https:\/\/www.wsmeguro.jp\/wp\/?p=4526"},"modified":"2025-01-13T15:16:05","modified_gmt":"2025-01-13T06:16:05","slug":"dart%e3%81%ae%e5%8b%89%e5%bc%b71%e2%88%923%ef%bc%9a%e9%85%8d%e5%88%97%ef%bc%88lists%ef%bc%89%e3%81%a8%e9%ab%98%e9%9a%8e%e9%96%a2%e6%95%b0%ef%bc%88methods%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.wsmeguro.jp\/wp\/?p=4526","title":{"rendered":"Dart\u306e\u52c9\u5f371\u22123\uff1a\u914d\u5217\uff08lists\uff09\u3068\u9ad8\u968e\u95a2\u6570\uff08methods\uff09"},"content":{"rendered":"<p>\u533f\u540d\u95a2\u6570\u306e\u524d\u306b\u914d\u5217\u3068\u9ad8\u968e\u95a2\u6570\u3092\u78ba\u8a8d\u3057\u305f\u65b9\u304c\u3044\u3044\u3068\u3044\u3046ChatGPT\u5148\u751f\u306e\u52a9\u8a00\u306b\u57fa\u3065\u3044\u3066\u3044\u307e\u3059\u3002<\/p>\n<ul>\n<li>\u914d\u5217\uff08lists\uff1aIn Dart, arrays are List objects, so most people just call them lists.\uff09<br \/>\n\u8907\u6570\u306e\u5024\u3092\u683c\u7d0d\u3067\u304d\u308b\u5909\u6570\u3068\u3044\u3046\u3053\u3068\u3067\u3044\u3044\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n<ol>\n<li>\u914d\u5217\u4f5c\u6210\uff08\u540c\u3058\u30c7\u30fc\u30bf\u578b\u306b\u3059\u308b\u306e\u304c\u57fa\u672c\uff09\n<div class=\"hcb_wrap\">\n<pre class=\"prism line-numbers lang-dart\" data-lang=\"Dart\">\r\n   var numbers = [1, 2, 3];\r\n   var colors = ['white','black','pink', 'cyan'];\r\n   List&lt;bool&gt;<bool> answers = [true, false];\r\n<\/pre>\n<\/div>\n<\/li>\n<li>\u914d\u5217\u306e\u64cd\u4f5c\u4f8b\n<div class=\"hcb_wrap\">\n<pre class=\"prism line-numbers lang-dart\" data-lang=\"Dart\">\r\nvoid main() {\r\n  var fruits = &lt;String&gt;[];\r\n  fruits.add('apples');\r\n  print(fruits); \/\/[apples]\r\n  fruits.addAll(['grapes', 'bananas', 'oranges']);\r\n  print(fruits); \/\/[apples, grapes, bananas, oranges]\r\n  var len = fruits.length; \/\/\u914d\u5217\u306e\u8981\u7d20\u6570\r\n  print(len); \/\/4\r\n  var appleIndex = fruits.indexOf('apples');\r\n  fruits.removeAt(appleIndex);\r\n  print(fruits); \/\/[grapes, bananas, oranges]\r\n  fruits.clear(); \/\/\u5168\u3066\u306e\u8981\u7d20\u3092\u524a\u9664\r\n  print(fruits); \/\/[]\r\n\r\n  var vegetables = List.filled(6, 'broccoli'); \/\/\u307e\u3068\u3081\u3066\u4f5c\u6210\r\n  print(vegetables); \/\/[broccoli, broccoli, broccoli, broccoli, broccoli, broccoli]\r\n}\r\n<\/pre>\n<\/div>\n<\/li>\n<\/ol>\n<li>\u9ad8\u968e\u95a2\u6570\uff08methods\uff09\n<ol>\n<li>forEach\n<div class=\"hcb_wrap\">\n<pre class=\"prism line-numbers lang-dart\" data-lang=\"Dart\">\r\nvoid main() {\r\n   var colors = ['white', 'black', 'pink', 'cyan'];\r\n   colors.forEach((color) {\r\n      print(color);\r\n   });\r\n}\r\n<\/pre>\n<\/div>\n<p>\u914d\u5217colors\u304b\u3089\uff11\u3064\u305a\u3064color\u3068\u3057\u3066\u53d6\u308a\u51fa\u3059\u30eb\u30fc\u30d7\u51e6\u7406\u3068\u306a\u3063\u3066\u3044\u307e\u3059\u3002<\/li>\n<li>map\n<div class=\"hcb_wrap\">\n<pre class=\"prism line-numbers lang-dart\" data-lang=\"Dart\">\r\nint doubleValue(int num) {\r\n  return num * 2;\r\n}\r\n\r\nvoid main() {\r\n  var numbers = [1, 2, 3, 4, 5, 6, 7];\r\n  var doubled = numbers.map(doubleValue).toList();\r\n  print(doubled);\r\n}\r\n<\/pre>\n<\/div>\n<p>\u500b\u4eba\u7684\u306b\u306f\u304b\u306a\u308a\u7406\u89e3\u306b\u82e6\u3057\u3093\u3060\u306e\u3067\u3059\u304c\u3001\u307e\u3068\u3081\u3066\u629c\u304d\u51fa\u3057\u3066\u3001\u307e\u3068\u3081\u3066\u51e6\u7406\u3059\u308b\u611f\u3058\u3067\u3059\u3002\u6700\u5f8c\u306btoList()\u3092\u3064\u3051\u3066List\u306b\u623b\u3059\u306e\u304c\u304a\u6c7a\u307e\u308a\u306e\u3088\u3046\u3067\u3059\u3002<\/li>\n<li>sort\n<div class=\"hcb_wrap\">\n<pre class=\"prism line-numbers lang-dart\" data-lang=\"Dart\">\r\nint ascendingOrder(int a, int b) {\r\n  return a - b; \/\/ a - b \u304c\u6bd4\u8f03\u7d50\u679c\r\n}\r\n\r\nint descendingOrder(int a, int b) {\r\n  return b - a; \/\/ b - a \u304c\u6bd4\u8f03\u7d50\u679c\r\n}\r\n\r\nvoid main() {\r\n  var numbers = [5, 2, 8, 1, 3];\r\n  numbers.sort(ascendingOrder); \/\/\u6b63\u306e\u5024\u3060\u3068a\u304c\u5927\u304d\u3044\u3068\u5224\u65ad\u3057\u3066a\u3068b\u3092\u5165\u308c\u66ff\u3048\r\n  print(numbers); \/\/ [1, 2, 3, 5, 8]\r\n  numbers.sort(descendingOrder); \/\/\u6b63\u306e\u5024\u3060\u3068b\u304c\u5927\u304d\u3044\u3068\u5224\u65ad\u3057\u3066a\u3068b\u3092\u5165\u308c\u66ff\u3048\r\n  print(numbers); \/\/ [8, 5, 3, 2, 1]\r\n}\r\n\r\n<\/pre>\n<\/div>\n<p>String\u306e\u5834\u5408\u306fcompareTo\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3063\u3066\u4e26\u3079\u66ff\u3048\u304c\u53ef\u80fd\u3067\u3059\u3002<\/p>\n<div class=\"hcb_wrap\">\n<pre class=\"prism line-numbers lang-dart\" data-lang=\"Dart\">\r\n\/\/ \u540d\u524d\u4ed8\u304d\u95a2\u6570\r\nint alphabeticalOrder(String a, String b) {\r\n  return a.compareTo(b);\r\n}\r\n\r\nvoid main() {\r\n  var names = ['Charlie', 'Alice', 'Bob'];\r\n\r\n  \/\/ \u540d\u524d\u4ed8\u304d\u95a2\u6570\u3092\u4f7f\u7528\u3057\u3066\u30bd\u30fc\u30c8\r\n  names.sort(alphabeticalOrder);\r\n\r\n  print(names); \/\/ ['Alice', 'Bob', 'Charlie']\r\n}\r\n<\/pre>\n<\/div>\n<\/ol>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>\u533f\u540d\u95a2\u6570\u306e\u524d\u306b\u914d\u5217\u3068\u9ad8\u968e\u95a2\u6570\u3092\u78ba\u8a8d\u3057\u305f\u65b9\u304c\u3044\u3044\u3068\u3044\u3046ChatGPT\u5148\u751f\u306e\u52a9\u8a00\u306b\u57fa\u3065\u3044\u3066\u3044\u307e\u3059\u3002 \u914d\u5217\uff08lists\uff1aIn Dart, arrays are List objects, so most people just&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"footnotes":""},"categories":[595,505],"tags":[601,597,618,619],"class_list":["post-4526","post","type-post","status-publish","format-standard","hentry","category-dart2","category-programming","tag-dart","tag-dart2","tag-dartpad"],"_links":{"self":[{"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/posts\/4526","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4526"}],"version-history":[{"count":11,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/posts\/4526\/revisions"}],"predecessor-version":[{"id":4538,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/posts\/4526\/revisions\/4538"}],"wp:attachment":[{"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4526"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4526"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4526"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}