在Dart中使用JsonObject库解析JSON列表 [英] Parsing JSON list with JsonObject library in Dart
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问题描述
我试图解析一些JSON与JsonOject库的帮助。我收到以下异常:
I'm trying to parse some JSON with the help of the JsonOject library. I'm getting the following exception:
Exception: type 'List' is not a subtype of type 'Map' of 'value'.
我的代码:
class MyList extends JsonObject implements List {
MyList();
factory MyList.fromString(String jsonString) {
return new JsonObject.fromJsonString(jsonString, new MyList());
}
}
class MyResult extends JsonObject {
num Dis;
int Flag;
MyProduct Obj;
}
class MyProduct extends JsonObject {
int ID;
String Title;
}
我这样调用:
var testJson = """
[{"Dis":1111.1,"Flag":0,"Obj":{"ID":1,"Title":"Volvo 140"}},
{"Dis":2222.2,"Flag":0,"Obj":{"ID":2,"Title":"Volvo 240"}}]
""";
MyList list = new MyList.fromString(testJson);
//I want to be able to do something like this.
//print(list[0].Obj.Title);
我在这里做错了什么?
推荐答案
我更新了我的 JsonObject github repo 来修复此错误。我还添加了传递单元测试,可再现此内容。
I've updated my JsonObject github repo to fix this bug. I've also added a passing unit test that reproduces this.
您需要运行 pub update
才能获取最新版本的库。
You'll need to run pub update
to get the latest version of the library.
以下代码现在可以工作:
The following code now works:
import 'package:json_object/json_object.dart';
void main() {
var testJson = """
[{"Dis":1111.1,"Flag":0,"Obj":{"ID":1,"Title":"Volvo 140"}},
{"Dis":2222.2,"Flag":0,"Obj":{"ID":2,"Title":"Volvo 240"}}]""";
MyList list = new MyList.fromString(testJson);
//I want to be able to do something like this.
print(list[0].Obj.Title); // <- now prints "Volvo 140"
}
class MyList extends JsonObject implements List {
MyList();
factory MyList.fromString(String jsonString) {
return new JsonObject.fromJsonString(jsonString, new MyList());
}
}
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