NodeJs中返回的head头声明

var http = require(‘http‘);

var obj = http.createServer(function(req, res){
    
    res.writeHead(200, ‘‘, {
        ‘content-type‘:‘text/html;charset=utf-8‘
    });

    res.write(‘<h1>hello world</h1>‘);

    res.end();
});

obj.listen(8080);

var http = require(‘http‘);

var obj = http.createServer(function(req, res){
    
    res.writeHead(200, ‘‘, {
        ‘content-type‘:‘text/plain‘
    });

    res.write(‘<h1>hello world</h1>‘);

    res.end();
});

obj.listen(8080);