我是node.js的新手。我不确定是我的代码还是我的计算机系统导致了这个问题。localhost：3000\login拒绝连接。我的代码

const http = require('http');

var server = http.createServer((req,res)=>{
    body = [];

    req.on('error',(err)=>{
        console.log(error);
    }).on("data",(chunkdata)=>{
        body.push(chunkdata);
        console.log(chunkdata.toString());
    }).on("end",()=>{
        body = Buffer.concat(body).toString();
        if(req.method =="POST"){
            if(req.url=="/login"){
                console.log(body)
                var user = JSON.parse(body);
                const {username,password} = user;
                res.statusCode =200;
                res.setHeader("Content-Type","application/json");
                res.write("Your usename is "+username +"and password is "+password );
                res.end();
            }
        }
    })

})

server.listen(3000,() => { 
  console.log("Server connected");
});

你能帮我解决这个问题吗？
我试着使用Postman，它工作正常