flutter 反序列化

一、内联反序列化

把JSON字符串转换成 Map<String, dynamic> 或者 List<dynamic>

import 'dart:convert';

main(List<String> args) {
  JsonCodec json = new JsonCodec();

  String str = '{"name":"tom"}';
  Map<String, dynamic> a = json.decode(str);
  print(a["name"]);

  String str1 = '["a","b"]';
  List<dynamic> b = json.decode(str1);
  print(b.length);

  String str3 = '{"name": "John Smith","email": "john@example.com"}';
  var c = json.decode(str3);
  print(c.runtimeType); //Map<String, dynamic>

  String str4 = '{"name": "John Smith","email": ["a","b"]}';
  var d = json.decode(str4);
  print(d.runtimeType); //Map<String, dynamic>

  String str5 = '{"name": "John Smith","email": {"a":"o","b":"p"}}';
  var e = json.decode(str5);
  print(e.runtimeType); //<String, dynamic>


  // String str6 = '{"name": "John Smith","email": {"a","b"}}';
  // var f = json.decode(str6); //FormatException: Unexpected character 报错
  // print(e.runtimeType);
}

 复杂些的比如

'{"age":19,"name":["tom","liu","wu"]}'    ？？

 

 

二、把字符串转成类对象

import 'dart:convert';

main(List<String> args) {
  String str = '{"age":19,"name":"tom"}';
  Map map = jsonDecode(str);
  Student user = Student.ds(map);
  print(user.age);
}

class Student {
  int age;
  String name;
  //Student(this.age, this.name);
  Student.ds(Map<String, dynamic> json)
      : age = json['age'],
        name = json['name'];
}

三、自动反序列化

使用 json_serializable    https://pub.dev/packages/json_serializable