如何在地图列表中提取数据并将其转换为dart中的地图答案

【问题标题】：how to extract data inside the list of maps and convert it into maps in dart如何在地图列表中提取数据并将其转换为dart中的地图
【发布时间】：2021-02-06 20:29:05
【问题描述】：

如何提取地图列表中的数据并将其转换为飞镖中的地图。 就像我有一张地图列表 ==================================== ==================================================== ==================================================== ==================================================== ======

[
  {"business_id":"2",
   "business_title":"Spotify",
   "business_phone":"(055) 3733783",
   "business_email":"Usamashafiq309@gmail.com",
   "business_website":"www.spotify.com",
   "business_address":"Spotify AB, Regeringsgatans bro, Stockholm, Sweden",
   "business_address_longitude":"18.0680873",
   "business_address_latitude":"59.33096949999999",
   "business_image":"5f84c7a4bbbd0121020201602537380.png",
   "business_created_at":"2020-10-20 15:40:17",
   "business_category_id":"2",
   "cat_id":"2",
   "cat_title":"Gym",
   "cat_image":"280920201601308237.png"}
    ,{"business_id":"2",
   "business_title":"Spotify",
   "business_phone":"(055) 3733783",
   "business_email":"Usamashafiq309@gmail.com",
   "business_website":"www.spotify.com",
   "business_address":"Spotify AB, Regeringsgatans bro, Stockholm, Sweden",
   "business_address_longitude":"18.0680873",
   "business_address_latitude":"59.33096949999999",
   "business_image":"5f84c7a4bbbd0121020201602537380.png",
   "business_created_at":"2020-10-20 15:40:17",
   "business_category_id":"2",
   "cat_id":"2",
   "cat_title":"Gym",
   "cat_image":"280920201601308237.png"}
 ]

并像这样转换它

[ {"business_id":"2",
   "business_title":"Spotify",},
 {"business_id": "1",
            "business_title": "Pizza Hut",},

]

【问题讨论】：

这是可以通过简单的在线研究轻松实现的。如果它仍然不起作用，那么您需要添加您尝试过的内容与您观察到的内容。检查minimal, reproducible example
谢谢下次我会小心的。 @JoyTerence

标签： list flutter dart set

【解决方案1】：

您可以使用map 函数将函数应用于列表的每个元素。然后你可以用你的地图创建一个子地图。

这是一个简单的例子：

void main() async {
  List l = [
    {
      "business_id": "2",
      "business_title": "Spotify",
      "business_phone": "(055) 3733783",
    },
    {
      "business_id": "1",
      "business_title": "Pizza Hut",
      "business_phone": "(055) 9999999",
    }
  ];

  print(extractMap(l));
}

List extractMap(List l) {
  return l
      .map((element) => Map.fromEntries([
            MapEntry('business_id', element['business_id']),
            MapEntry('business_title', element['business_title']),
          ]))
      .toList();
}

【讨论】：