var url = require('url');

/* url.parse(urlString[,parseQueryString[,slashesDenoteHost]])
 * urlString <string>将被解析的网址
 * parseQueryString <boolean> 默认为false，将query解析成一个字符串；如何设为true，则将query解析成一个对象
 * @return <object>
 */
var result = url.parse('https://www.baidu.com/s?ie=UTF-8&wd=node.js')
console.log(result);
// 打印结果
{
 protocol: 'https:', // url协议
 slashes: true, // 斜线'/'
 auth: null, // 用户认证
 host: 'www.baidu.com', // 主机
 port: null, // 端口
 hostname: 'www.baidu.com', // 主机名
 hash: null, // hash 值
 search: '?ie=UTF-8&wd=node.js', // url中查询信息，包含'?'
 query: 'ie=UTF-8&wd=node.js', // url中查询信息，不包含'?'
 pathname: '/s', // 跟在host之后的整个文件路径
 path: '/s?ie=UTF-8&wd=node.js', // pathname和search
 href: 'https://www.baidu.com/s?ie=UTF-8&wd=node.js' // 元素url
}

var urlObj = {
 protocol:'http',
 host:'www.baidu.com',
 pathname:'/page',
 search:'?index=1&sign=true'
}
var urlStr = url.format(urlObj);
console.log(urlStr);
// 打印结果
// http://www.baidu.com/page?index=1&sign=true

var urlStr = url.resolve('http://www.baidu.com/','page');
console.log(urlStr);
// 打印结果
// http://www.baidu.com/page

var urlStr1 = url.resolve('/page/person/','pic');
console.log(urlStr1);
// 打印结果
// /page/person/pic