做网站建设培训软文推广营销
题记
node.js中express框架的用法
Express框架的特点
可以设置中间件来响应 HTTP 请求。
定义了路由表用于执行不同的 HTTP 请求动作。
可以通过向模板传递参数来动态渲染 HTML 页面。
安装Express模块
npm install express --save
安装重要模块
npm install body-parser --save
npm install cookie-parser --save
npm install multer --save
查看express版本
npm list express
请求和响应
语法:
app.get('/', function (req, res) {
// --
})
创建实例
创建main.js实例:
//main.js 文件
var express = require('express');
var app = express();app.get('/', function (req, res) {res.send('Hello World');
})var server = app.listen(8080, function () {var host = server.address().addressvar port = server.address().portconsole.log("应用实例,访问地址为 http://%s:%s", host, port)})
路由
var express = require('express');
var app = express();// 主页输出 "Hello World"
app.get('/', function (req, res) {console.log("主页 GET 请求");res.send('Hello GET');
})// POST 请求
app.post('/', function (req, res) {console.log("主页 POST 请求");res.send('Hello POST');
})// /del_user 页面响应
app.get('/del_user', function (req, res) {console.log("/del_user 响应 DELETE 请求");res.send('删除页面');
})// /list_user 页面 GET 请求
app.get('/list_user', function (req, res) {console.log("/list_user GET 请求");res.send('用户列表页面');
})// 对页面 abcd, abxcd, ab123cd, 等响应 GET 请求
app.get('/ab*cd', function(req, res) { console.log("/ab*cd GET 请求");res.send('正则匹配');
})var server = app.listen(8080, function () {var host = server.address().addressvar port = server.address().portconsole.log("应用实例,访问地址为 http://%s:%s", host, port)})
静态文件
语法:
app.use('/public', express.static('public'));
创建main.js代码:
var express = require('express');
var app = express();app.use('/public', express.static('public'));app.get('/', function (req, res) {res.send('Hello World');
})var server = app.listen(8080, function () {var host = server.address().addressvar port = server.address().portconsole.log("应用实例,访问地址为 http://%s:%s", host, port)})
GET方法
创建index.html:
<html>
<body>
<form action="http://127.0.0.1:8080/process_get" method="GET">
First Name: <input type="text" name="first_name"> <br>Last Name: <input type="text" name="last_name">
<input type="submit" value="Submit">
</form>
</body>
</html>
创建server.js文件:
var express = require('express');
var app = express();app.use('/public', express.static('public'));app.get('/index.html', function (req, res) {res.sendFile( __dirname + "/" + "index.html" );
})app.get('/process_get', function (req, res) {// 输出 JSON 格式var response = {"first_name":req.query.first_name,"last_name":req.query.last_name};console.log(response);res.end(JSON.stringify(response));
})var server = app.listen(8080, function () {var host = server.address().addressvar port = server.address().portconsole.log("应用实例,访问地址为 http://%s:%s", host, port)})
POST方法
创建index.html:
<html>
<body>
<form action="http://127.0.0.1:8080/process_post" method="POST">
First Name: <input type="text" name="first_name"> <br>Last Name: <input type="text" name="last_name">
<input type="submit" value="Submit">
</form>
</body>
</html>
创建server.js:
var express = require('express');
var app = express();
var bodyParser = require('body-parser');// 创建 application/x-www-form-urlencoded 编码解析
var urlencodedParser = bodyParser.urlencoded({ extended: false })app.use('/public', express.static('public'));app.get('/index.html', function (req, res) {res.sendFile( __dirname + "/" + "index.html" );
})app.post('/process_post', urlencodedParser, function (req, res) {// 输出 JSON 格式var response = {"first_name":req.body.first_name,"last_name":req.body.last_name};console.log(response);res.end(JSON.stringify(response));
})var server = app.listen(8080, function () {var host = server.address().addressvar port = server.address().portconsole.log("应用实例,访问地址为 http://%s:%s", host, port)})
上传文件
创建index.html:
<html>
<head>
<title>文件上传表单</title>
</head>
<body>
<h3>文件上传:</h3>
选择一个文件上传: <br />
<form action="/file_upload" method="post" enctype="multipart/form-data">
<input type="file" name="image" size="50" />
<br />
<input type="submit" value="上传文件" />
</form>
</body>
</html>
创建server.js:
var express = require('express');
var app = express();
var fs = require("fs");var bodyParser = require('body-parser');
var multer = require('multer');app.use('/public', express.static('public'));
app.use(bodyParser.urlencoded({ extended: false }));
app.use(multer({ dest: '/tmp/'}).array('image'));app.get('/index.html', function (req, res) {res.sendFile( __dirname + "/" + "index.html" );
})app.post('/file_upload', function (req, res) {console.log(req.files[0]); // 上传的文件信息var des_file = __dirname + "/" + req.files[0].originalname;fs.readFile( req.files[0].path, function (err, data) {fs.writeFile(des_file, data, function (err) {if( err ){console.log( err );}else{response = {message:'File uploaded successfully', filename:req.files[0].originalname};}console.log( response );res.end( JSON.stringify( response ) );});});
})var server = app.listen(8080, function () {var host = server.address().addressvar port = server.address().portconsole.log("应用实例,访问地址为 http://%s:%s", host, port)})
Cookie管理
创建main.js文件:
// express_cookie.js 文件
var express = require('express')
var cookieParser = require('cookie-parser')
var util = require('util');var app = express()
app.use(cookieParser())app.get('/', function(req, res) {console.log("Cookies: " + util.inspect(req.cookies));
})app.listen(8080)
后记
觉得有用可以点赞或收藏!