{"id":4541,"date":"2025-01-13T16:45:37","date_gmt":"2025-01-13T07:45:37","guid":{"rendered":"https:\/\/www.wsmeguro.jp\/wp\/?p=4541"},"modified":"2025-01-13T17:14:44","modified_gmt":"2025-01-13T08:14:44","slug":"dart%e3%81%ae%e7%b7%b4%e7%bf%921%e2%88%924%ef%bc%9amap%e5%9e%8b","status":"publish","type":"post","link":"https:\/\/www.wsmeguro.jp\/wp\/?p=4541","title":{"rendered":"Dart\u306e\u7df4\u7fd21\u22124\uff1aMap\u578b"},"content":{"rendered":"

Map\u578b\u306f\u3001\u30ad\u30fc\u3068\u5024\u306e\u30da\u30a2\u3067\u30c7\u30fc\u30bf\u3092\u7ba1\u7406\u3059\u308b\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u3067\u3059\u3002<\/p>\n

    \n
  1. Map\u306e\u4f5c\u6210\n
    \n
    \r\nvoid main() {\r\n  var map = {\r\n    'name':'Japan',\r\n    'population':128057,\r\n    'area':377973,\r\n  };\r\n  print(map); \/\/{name: Japan, population: 128057, area: 377973}\r\n}\r\n\u578b\u3092\u6307\u5b9a\u3057\u3066\u4f5c\u6210\r\nvoid main() {\r\n  Map map = {\r\n    'Japan': 128057,\r\n    'India': 1210855,\r\n    'Canada': 33477,\r\n  };\r\n  print(map); \/\/{Japan: 128057, India: 1210855, Canada: 33477}\r\n}\r\n<\/pre>\n<\/div>\n<\/li>\n
  2. Map\u306e\u64cd\u4f5c\n
    \n
    \r\nvoid main() {\r\n  Map map = {\r\n    'Japan': 128057,\r\n    'India': 1210855,\r\n    'Canada': 33477,\r\n  };\r\n  \/\/\u5024\u306e\u53d6\u5f97\r\n  print(map['Japan']); \/\/128057\r\n  \/\/\u5024\u306e\u8ffd\u52a0\r\n  map['Tempest'] = 112337;\r\n  print(map); \/\/{Japan: 128057, India: 1210855, Canada: 33477, Tempest: 112337}\r\n  \/\/\u5024\u306e\u66f4\u65b0\r\n  map['Tempest'] = 123;\r\n  print(map); \/\/{Japan: 128057, India: 1210855, Canada: 33477, Tempest: 123}\r\n  \/\/\u5024\u306e\u524a\u9664\r\n  map.remove('Tempest');\r\n  print(map); \/\/{Japan: 128057, India: 1210855, Canada: 33477}\r\n  \/\/\u5168\u3066\u306e\u30ad\u30fc\u3084\u5024\u306e\u53d6\u5f97\r\n  print(map.keys); \/\/(Japan, India, Canada)\r\n  print(map.values); \/\/(128057, 1210855, 33477)\r\n  \/\/\u30ad\u30fc\u3084\u5024\u306e\u5b58\u5728\u78ba\u8a8d\r\n  print(map.containsKey('Japan')); \/\/ true\r\n  print(map.containsValue(123)); \/\/ false\r\n\r\n  \/\/Map\u306e\u5168\u8981\u7d20\u3092\u30eb\u30fc\u30d7\r\n  map.forEach((key, value) {\r\n    print('$key: $value');\r\n  });\r\n  \/\/ Japan: 128057\r\n  \/\/ India: 1210855\r\n  \/\/ Canada: 33477\r\n\r\n  \/\/\u30ad\u30fc\u3068\u5024\u3092\u4f7f\u3063\u305f\u51e6\u7406\r\n  for (var entry in map.entries) {\r\n    print('The population of ${entry.key} is ${entry.value} K');\r\n  }\r\n  \/\/ The population of Japan is 128057 K\r\n  \/\/ The population of India is 1210855 K\r\n  \/\/ The population of Canada is 33477 K\r\n\r\n}\r\n<\/pre>\n<\/div>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"
    Map\u578b\u306f\u3001\u30ad\u30fc\u3068\u5024\u306e\u30da\u30a2\u3067\u30c7\u30fc\u30bf\u3092\u7ba1\u7406\u3059\u308b\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u3067\u3059\u3002 Map\u306e\u4f5c\u6210 void main() { var map = { ‘name’:’Japan’, ‘population’:128057, ‘area’:3…<\/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":[601,618,619],"class_list":["post-4541","post","type-post","status-publish","format-standard","hentry","category-dart2","category-programming","tag-dart","tag-dartpad"],"_links":{"self":[{"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/posts\/4541","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=4541"}],"version-history":[{"count":1,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/posts\/4541\/revisions"}],"predecessor-version":[{"id":4542,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=\/wp\/v2\/posts\/4541\/revisions\/4542"}],"wp:attachment":[{"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4541"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4541"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wsmeguro.jp\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4541"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}