Flutter如何做JSON序列化

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我该用什么JSON序列化方式?

其实大型项目使用手动+借助下面提到的在线转换的方式更加灵活高效;

如何反序列化?

String jsonStr = '{ "icon": "http://www.devio.org/io/flutter_app/img/ln_food.png", "title": "美食林", "url": "https://m.ctrip.com/webapp/you/foods/address.html?new=1&ishideheader=true", "statusBarColor": "19A0F0", "hideAppBar": true }';
​
Map<String, dynamic> map = JSON.decode(jsonStr);
 
print('icon: ${map['icon']}');
print('title:${map['title']}');

通过上述方式可以将json字符串转换成Map,但Map中存放那些字段在使用的时候很不方便,如果将Map转成Model呢?

...
CommonModel model = CommonModel.fromJson(map);
print('icon: ${model.icon}');
print('title:${model.title}');
 
...
class CommonModel {
  final String icon;
  final String title;
  final String url;
  final String statusBarColor;
  final bool hideAppBar;
 
  CommonModel({this.icon, this.title, this.url, this.statusBarColor, this.hideAppBar});
 
  factory CommonModel.fromJson(Map<String, dynamic> json) {
    return CommonModel(
      icon: json['icon'],
      title: json['title'],
      url: json['url'],
      statusBarColor: json['statusBarColor'],
      hideAppBar: json['hideAppBar'],
    );
  }
}

这样一来我们就可以很明确的指导model中有那些字段。

复杂JSON解析?

数组

{
  "url": "xxx",
  "tabs": [
    {
      "labelName": "推荐",
      "groupChannelCode": "tourphoto_global1"
    },
    {
      "labelName": "拍照技巧",
      "groupChannelCode": "tab-photo"
    }
  ]
}

解析:

class TravelTabModel {
  String url;
  List<TravelTab> tabs;
 
  TravelTabModel({this.url, this.tabs});
 
  TravelTabModel.fromJson(Map<String, dynamic> json) {
     url = json['url'];
    (json['tabs'] as List).map((i) => TravelTab.fromJson(i));
  }
}
 
class TravelTab {
  String labelName;
  String groupChannelCode;
 
  TravelTab({this.labelName, this.groupChannelCode});
 
  TravelTab.fromJson(Map<String, dynamic> json) {
    labelName = json['labelName'];
    groupChannelCode = json['groupChannelCode'];
  }
}

如果要加些异常处理:

TravelTabModel.fromJson(Map<String, dynamic> json) {
    url = json['url'];
    if (json['tabs'] != null) {
      tabs = new List<TravelTab>();
      json['tabs'].forEach((v) {
        tabs.add(new TravelTab.fromJson(v));
      });
    }
  }

改成final:

class TravelTabModel {
  final String url;
  final List<TravelTab> tabs;
 
  TravelTabModel({this.url, this.tabs});
 
  factory TravelTabModel.fromJson(Map<String, dynamic> json) {
    String url = json['url'];
    List<TravelTab> tabs =
        (json['tabs'] as List).map((i) => TravelTab.fromJson(i)).toList();
    return TravelTabModel(url: url, tabs: tabs);
  }
}

在线转换工具

JSON to Dart

JSON转dart-BeJSON.com