如何将从cloud_firestore接收的数据转换为Map [英] How to transform the data received from cloud_firestore into a Map

问题描述

cloud_firestore数据库中的数据为JSON形式。但是，如何从Map列表中的JSON转换数据？
我的Firestore中的虚拟数据

The data from the cloud_firestore database is in the form of JSON. However, how to transform the data from JSON in a List of Map? The dummy data in my firestore

推荐答案

数据到地图列表：

final CollectionReference ref = Firestore.instance.collection('food');
List<Map<String, dynamic>> listOfMaps = [];
await ref.getDocuments().then((QuerySnapshot snapshot) {
  listOfMaps =
      snapshot.documents.map((DocumentSnapshot documentSnapshot) {
    return documentSnapshot.data;
  }).toList();
});
print(listOfMaps);

以防万一，如果您想使用更好的方法。将数据解析为对象列表：

Just in case if You want to use better way. Parse data to List of Objects:

1）创建模型类：

class Food {
  String affordability;
  String title;

  Food.fromJson(Map<String, dynamic> jsonData) {
    this.affordability = jsonData['affordability'];
    this.title = jsonData['title'];
  }
}

2）转换为食物列表：

2) convert to list of Food:

final CollectionReference ref = Firestore.instance.collection('food');
List<Food> list = [];
await ref.getDocuments().then((QuerySnapshot snapshot) {
  list = snapshot.documents.map((DocumentSnapshot documentSnapshot) {
    return Food.fromJson(documentSnapshot.data);
  }).toList();
});
print(list);

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