[JavaScript知识库]NodeJS学习

内置API

1.fs

文件的读写

const fs = require('fs');

fs.writeFile(__dirname+'/file/text.txt','小红=20 小明=60 小刚=40 小强=80',function(erro){
    if(erro)
        console.log(erro);
    else{
        fs.readFile(__dirname+'/file/text.txt','utf-8',function(err,datastr){
            if(err)
                return console.log(erro);
            console.log(datastr)
            const arr = datastr.split(' ');
            console.log(arr) 
            const arr1 = [] 
            arr.forEach(element => {
                arr1.push(element.replace('=',"："))
            });
            console.log(arr1)
            const arr2 = arr1.join('\r\n')
            console.log(arr2)
        });

    }
    
})

2.path

路径操作

const path = require('path')
const pathstr = path.join(__dirname,'/file','/text.txt')
const fs = require('fs')
fs.readFile(pathstr,'utf-8',function(error,data){
    if(error){
        return console.log(error)
    }else
        console.log(data)
})
console.log(path.basename(pathstr))
console.log(path.basename(pathstr,'.txt'))
console.log(path.extname(pathstr))

3.http

服务器相关

const http = require('http')
const server = http.createServer()
server.on('request', (req,res) => {
    const url = req.url
    const method = req.method
    let content = '<h1>404 Not Found!!!</h1>'
    if (url === '/' || url === '/index.html'){
        content = '<h1>主页</h1>'
    }else if(url === '/shop.html'){
        content = '<font color="red">商店</font>'
    }
    res.setHeader('Content-Type','text/html; charset=utf-8')
    //res.end(`访问的 url 是 ${url}, 访问的方法是 ${method}`)
    res.end(content)
})

server.listen(80,function(){
    console.log('server running at http://127.0.0.1')
})

第三方API

npm init -y:创建pakage.json
npm i 包名[@版本号]:导入第三方包
npm i 包名[@版本号] -D:导入第三方包，但只是开发阶段使用
npm i:导入pakage.json中所依赖的所有包
npm uninstall 包名:卸载第三方包
//1.切换镜像
npm config get registry:获取当前下载的镜像源地址
npm config set registry=https://registry.npm.taobao.org/
//2.切换镜像
npm i nrm -g
nrm ls:查看可用镜像源
nrm use taobao