This time I will bring you the image upload effect of angular2 nodejs. What are the precautions for image upload effect of angular2 nodejs? The following is a practical case, let's take a look.
nodejs backend code代码如下 varexpress = require("express"); //网络请求模块 varrequest = require("request"); //引入nodejs文件系统模块 const fs = require('fs'); //引入body-parser //包含在请求正文中提交的键/值对数据。 //默认情况下,它是未定义的,并在使用body-parser中间件时填充。 varbodyParser = require('body-parser'); varapp = express(); //解析 application/x-www-form-urlencoded,limit:ཐmb'用于设置请求的大小 //解决nodejs Error: request entity too large问题 app.use(bodyParser.urlencoded({ limit:ཐmb',extended:true})); //设置跨域访问 app.all('*',function(req, res, next) { res.header("Access-Control-Allow-Origin","*"); res.header("Access-Control-Allow-Headers","X-Requested-With"); res.header("Access-Control-Allow-Methods","PUT,POST,GET,DELETE,OPTIONS"); res.header("Content-Type","application/json;charset=utf-8"); next(); }); //上传图片 app.post('/upload',function(req,res){ varimgData = req.body.url; varbase64Data = imgData.replace(/^data:image\/\w+;base64,/,""); vardataBuffer =newBuffer(base64Data,'base64'); fs.writeFile("image.png", dataBuffer,function(err) { if(err){ res.send(err); }else{ res.send("保存成功!"); } }); }) varserver = app.listen(4444,function() { console.log('监听端口 4444'); });angular2 frontend code
//上传图片 /* * let data = { * size: �', * type: 'image/jpeg', * name: 'test.jpg', * url: base64 * }; *获取图片的base64码可以通过FileReader获取 */ uploadImage(data) { returnnewPromise((resolve, reject) => { let headers =newHeaders({ 'Content-Type':'application/x-www-form-urlencoded' }); let options =newRequestOptions({ headers: headers }); this.http.post("http://localhost:4444/upload",this.toQueryString(data),options) .map(res => res.json()) .subscribe(data => { resolve(data), error => { reject(error) } }) }) } // JSON参数序列化 private toQueryString(obj) { let result = []; for(let keyinobj) { key = encodeURIComponent(key); let values = obj[key]; if(values && values.constructor == Array) { let queryValues = []; for(let i = 0, len = values.length, value; i I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website! <p style="text-align: left;"></p>Recommended reading: <p style="text-align: left;"></p><p style="text-align: left;">JS implementation of drop-down menu login registration pop-up window<a href="http://www.php.cn/js-tutorial-393368.html" target="_blank"></a></p><p style="text-align: left;">How to deal with http hijacked floating ads<a href="http://www.php.cn/js-tutorial-393365.html" target="_blank"></a></p><p style="text-align: left;">Summary of methods to improve Node.js performance<a href="http://www.php.cn/js-tutorial-393357.html" target="_blank"></a></p>
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Python is more suitable for data science and automation, while JavaScript is more suitable for front-end and full-stack development. 1. Python performs well in data science and machine learning, using libraries such as NumPy and Pandas for data processing and modeling. 2. Python is concise and efficient in automation and scripting. 3. JavaScript is indispensable in front-end development and is used to build dynamic web pages and single-page applications. 4. JavaScript plays a role in back-end development through Node.js and supports full-stack development.

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JavaScript's application in the real world includes front-end and back-end development. 1) Display front-end applications by building a TODO list application, involving DOM operations and event processing. 2) Build RESTfulAPI through Node.js and Express to demonstrate back-end applications.

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