一、目录
1、访问网页
2、http请求
-----------------------------这是分割线-----------------------------
1、访问网页
基于url_launcher库实现，最新版本号 5.0.2，没有的话需要添加到pubspec.yaml中
然后get 该package
只要引入不报错就ok了。
ex.dart
/*
time: 2019-4-3
*/ // 引入资源包
import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart'; // main fun
void main() => runApp(new MyApp()); class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
// TODO: implement build
return new MaterialApp(
title: 'url请求',
home: new Scaffold(
appBar: new AppBar(
title: new Text('Example of packages'),
),
body: new Center(
child: new RaisedButton(
onPressed: () {
print();
// url
const url = "https://www.baidu.com";
launch(url); // 打开浏览器跳转至百度网页
},
child: new Text('baidu'),
),
),
));
}
}
运行效果如下
点击baidu按钮，打开网页
2、http请求
2.1、Http请求
下载Http库 版本号 0.12.0+2
ex.dart
/*
time: 2019-4-3
title: htttp请求
*/ // 引入资源包
import 'package:flutter/material.dart';
//import 'package:url_launcher/url_launcher.dart';
import 'package:http/http.dart' as http; // main fun
void main () => runApp(new MyApp()); class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
// TODO: implement build
return new MaterialApp(
title: 'Http 请求示例',
home: new Scaffold(
appBar: new AppBar(
title: new Text('Http 请求示例'),
),
body: new Center(
child: new RaisedButton(
onPressed: () {
print();
var url = 'http://www.cnblogs.com/'; // get
http.get(url).then((response) {
print("Response status: ${response.statusCode}");
print("Response body: ${response.body[10]}");
}); // post
http.post(url,body: {"key": "value"}).then((response) {
print('this is post');
print("Response status: ${response.statusCode}");
print("Response body: ${response.body}");
});
},
child: new Text('发送请求'),
),
),
)
);
}
}
运行效果
我点击发送请求之后，控制台输出
请求成功，并返回了内容。
2.1、HttpClient请求
ex.dart
/*
time: 2019-4-3
title: htttpClient请求
*/ // 引入资源包
import 'package:flutter/material.dart';
import 'dart:convert';
import 'dart:io'; // main fun
void main () => runApp(new MyApp()); class MyApp extends StatelessWidget {
// 获取天气数据
void getWeatherData() async {
try {
// 实例化一个HttpCLient对象
HttpClient httpClient = new HttpClient(); // 发起请求
HttpClientRequest request = await httpClient.getUrl(
Uri.parse("http://wthrcdn.etouch.cn/weather_mini?city=重庆市")
);
// 等待服务器返回数据
HttpClientResponse response = await request.close();
// 使用utf-8.decoder从response解析数据
var result = await response.transform(utf8.decoder).join();
// 输出
print(result);
// 关闭
httpClient.close(); } catch (e) {
print("请求失败：$e");
}
}
@override
Widget build(BuildContext context) {
// TODO: implement build
return new MaterialApp(
title: 'HttpClient 请求示例',
home: new Scaffold(
appBar: new AppBar(
title: new Text('HttpClient 请求示例'),
),
body: new Center(
child: new RaisedButton(
onPressed: getWeatherData,
child: new Text('获取天气数据'),
),
),
)
);
}
}
运行效果如下：
点击按钮之后，控制台输出：
I/flutter (15353): {"data":{"yesterday":{"date":"6日星期六","high":"高温 30℃","fx":"无持续风向","low":"低温 14℃","fl":"<![CDATA[<3级]]>","type":"晴"},"city":"重庆","forecast":[{"date":"7日星期天","high":"高温 32℃","fengli":"<![CDATA[<3级]]>","low":"低温 15℃","fengxiang":"无持续风向","type":"晴"},{"date":"8日星期一","high":"高温 32℃","fengli":"<![CDATA[<3级]]>","low":"低温 18℃","fengxiang":"无持续风向","type":"多云"},{"date":"9日星期二","high":"高温 29℃","fengli":"<![CDATA[<3级]]>","low":"低温 19℃","fengxiang":"无持续风向","type":"多云"},{"date":"10日星期三","high":"高温 24℃","fengli":"<![CDATA[<3级]]>","low":"低温 18℃","fengxiang":"无持续风向","type":"阴"},{"date":"11日星期四","high":"高温 25℃","fengli":"<![CDATA[<3级]]>","low":"低温 18℃","fengxiang":"无持续风向","type":"多云"}],"ganmao":"各项气象条件适宜，发生感冒机率较低。但请避免长期处于空调房间中，以防感冒。","wendu":"3}