json - 如何解析嵌套的JSON字典( map )

Question

我正在尝试将与Swift程序兼容的JSON代码读入Flutter应用程序。结构是这样的:

{
  "tagDict" : {
    "abc" : {
      "helpHdr" : "short text1",
      "helpText" : "long text1"
    },
    "def" : {
      "helpHdr" : "short text2",
      "helpText" : "long text2"
    }
  }
}

这将在Swift中创建一个字典，并在Dart中创建一个{key:{helpHdr，helpText}}类型的 map 。基于此的变量应启用label = myVariable [tag] .helpHdr，或与示例label = myVariable [“abc”]。helpHdr一起使用，应为标签分配“short text1”
为了解析嵌套数组，我正在使用它，但是，不知道如何将其传输到这样的嵌套映射。

class MyClass {
  List<MySubClass> myArray;
  MyClass({
    this.myArray,
  });

  factory MyClass.fromJson(Map<String, dynamic> parsedJson){
    var list = parsedJson['myArray'] as List;
    List<MySubClass> listObject = list.map((i) => MySubClass.fromJson(i)).toList();
    return new MyClass(
      myArray: listObject,
    );
  }
}

class MySubClass {
  int id;
  String text1;
  String text2;
  MySubClass({
    this.id,
    this.text1,
    this.text2,
  });

  factory MySubClass.fromJson(Map<String, dynamic> parsedJson){
    return new MySubClass(
      id: parsedJson['id'],
      text1: parsedJson['text1'],
      text2: parsedJson['text2'],
    );
  }
}

Answer 1

如果我是正确的，您想将json解析为Data类对象。如果是这样，那么您可以尝试一下

void main() {
  List<MyClass> myClassList = new List<MyClass>();
  Map map = {
    "tagDict": {
      "abc": {"helpHdr": "short text1", "helpText": "long text1"},
      "def": {"helpHdr": "short text2", "helpText": "long text2"}
    }
  };

  map['tagDict'].forEach((key, value) {
    value['id'] = key;
    myClassList.add(MyClass.fromJson(value));
  });

  myClassList.forEach((myClass) {
    print(myClass.id);
    print(myClass.helpHdr);
    print(myClass.helpText);
    print("--------------------\n");
  });
}

class MyClass {
  String id;
  String helpHdr;
  String helpText;

  MyClass({this.id, this.helpHdr, this.helpText});

  MyClass.fromJson(Map<String, dynamic> json) {
    id = json['id'];
    helpHdr = json['helpHdr'];
    helpText = json['helpText'];
  }

  Map<String, dynamic> toJson() {
    final Map<String, dynamic> data = new Map<String, dynamic>();
    data['id'] = this.id;
    data['helpHdr'] = this.helpHdr;
    data['helpText'] = this.helpText;
    return data;
  }
}

这是输出:

abc
short text1
long text1
--------------------

def
short text2
long text2
--------------------