我在我的大学服务器上托管了一个 php 文件，当我在服务器上运行该文件时，它运行良好。运行链接中的 php 文件后，我可以获得 json 数据 http://www.alkadhum-col.edu.iq/Teachers%20Activities/get.php但是当我在应用程序屏幕上 flutter 地尝试时，我无法得到。

首先，我尝试更改网址无效。其次，我试图将 json 对象转换为 .toString() 并且也不起作用。

import 'package:flutter/material.dart';
import 'package:http/http.dart' show get;
import 'dart:convert';

class Post {
  String name;
  String msg;
  String day;
  String date;

  Post({this.name, this.msg, this.day, this.date});

  factory Post.fromJson(Map<String, dynamic> json) {
    return Post(
      name: json['name'].toString(),
      msg: json['msg'].toString(),
      day: json['day'].toString(),
      date: json['date'].toString(),
    );
  }
}

class CustomListView extends StatelessWidget {

  List teachers = [];

  CustomListView(this.teachers);

  @override
  Widget build(BuildContext context) {
    return (
      ListView.builder(
        itemCount: teachers.length, 
        itemBuilder: (BuildContext context, int index) {
          return createviewItem(teachers[index], context);
        },
      )
    );
  }

  Widget createviewItem(Post teachers, BuildContext context) {
    return ListTile(
      title: new Card(
        child: new Container(
          decoration: BoxDecoration(border: Border.all(color: Colors.lightBlue)),
          padding: EdgeInsets.all(20.0),
          margin: EdgeInsets.all(20.0),
          child: Column(children: <Widget>[
            new Text(teachers.name),
            new Text(teachers.msg),
            new Text(teachers.day),
            new Text(teachers.date)
          ],),
        )
      )
    );
  }

}


Future<List<Post>> downloadJSON() async {
  final jsonEndpoint = "http://www.alkadhum-col.edu.iq/Teachers%20Activities/get.php";
  final response = await get(jsonEndpoint);
  if (response.statusCode == 200) {
    List teachers = json.decode(response.body);
    return teachers.map(
      (teacher) => new Post.fromJson(teacher)
    ).toList();
  }

  else {
    throw Exception("Unable to get JSON data");
  }
}


class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
    theme: new ThemeData(
    primarySwatch: Colors.deepOrange,
    ),
    home: new Scaffold(
    appBar: new AppBar(title: const Text('Flutter and PHP')),
    body: new Center(

    child: new FutureBuilder<List<Post>>(
    future: downloadJSON(),

    builder: (context, snapshot) {
    if (snapshot.hasData) {
    List<Post> teachers = snapshot.data;
    return new CustomListView(teachers);
    } else if (snapshot.hasError) {
    return Text('${snapshot.error}');
    }
    //return  a circular progress indicator.
    return new CircularProgressIndicator();
    },
    ),
    ),
    ),
    );
}
}
void main() {
runApp(MyApp());
}

我得到了格式异常:意外的字符(在字符 115 处)并且列表中的一些数据不是字符串形式。

最佳答案

问题是您的数据不是 JSON 数据。

[
  {
    "name": "م.م علي ستار باراني",
    "msg": "امتحان مادة قواعد البيانات اول جابترين ",
    "day": "السبت",
    "date": "2019-06-20"
  }
][
  {
    "name": "م. امجد عباس التميمي",
    "msg": "امتحان مادة هندسة البرامجيات اول فصلين",
    "day": "الاحد",
    "date": "2019-06-21"
  },
  {
    "name": "م.م علي ستار باراني",
    "msg": "امتحان مادة قواعد البيانات اول جابترين ",
    "day": "السبت",
    "date": "2019-06-20"
  }
]

问题出在这两个括号中:

  }
][
  {

JSON code should be like this.

[
  {
    "name": "م.م علي ستار باراني",
    "msg": "امتحان مادة قواعد البيانات اول جابترين ",
    "day": "السبت",
    "date": "2019-06-20"
  },
  {
    "name": "م. امجد عباس التميمي",
    "msg": "امتحان مادة هندسة البرامجيات اول فصلين",
    "day": "الاحد",
    "date": "2019-06-21"
  },
  {
    "name": "م.م علي ستار باراني",
    "msg": "امتحان مادة قواعد البيانات اول جابترين ",
    "day": "السبت",
    "date": "2019-06-20"
  }
]

关于php - 如何从服务器上的php文件获取json数据到flutter应用程序，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/56714770/