Flutter:如何在Map内访问数组数据? [英] Flutter: How to access array data inside a Map?

问题描述

我正在开发Flutter应用，并且正在获取如下所示的JSON数据

I am developing a Flutter app and I am getting a JSON data like below

{chat_mode: supplier, timestamp: 1605852885271, last_message: Test, members: [K9ioYyiEUQVVNjx0owwsABCD, K9ioYyiEUQVVNjx0owwsaXYZ]}

我需要访问 members 下的每个单独元素，这是我尝试过的.

I need to access each individual element under members and this is what I tried.

Map<dynamic, dynamic> map = snapshot.value;
print(map["members"]);

以上内容使我可以访问整个数组，而不是每个记录.

The above allows me to access the entire array, not each record.

但是我无法通过使用诸如 map ["members"] [0] 之类的东西来访问单个元素，因为它是一个地图.在这种情况下，我该如何访问这些数据?

But i can't access the individual element by using something like map["members"][0] because it is a map. In this case, how can i access this data?

推荐答案

您必须将其显式转换为 List

You have to explicitly convert it to a List

尝试

List<dynamic> members = List.of(map["members"]);

或

List<dynamic> members = map["members"];

这篇关于Flutter:如何在Map内访问数组数据?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！