基础

app.get('/hi', (req, res) => {
  res.render('hello World!!!');
});

app.get('/err', (req, res) => {
  res.status(404);
  res.render('404 ， NO Find!!!');
  /**
   * res.status(404).render('404 , NO Find!!!'); // 一行更比两行强
   */
});

app.get('/login', (req, res) => {
  res.render('can', {
    message: 'welcome',
    style: req.query.style,
    userid: req.cookie.userid,
    username: req.session.username,
  });
});

app.get('/noLayout', (req, res) => {
  res.render('no-layout', { layout: null });
});

app.get('/customLayout', (req, res) => {
  res.render('custom-layout', { layout: 'custom' });
});

app.get('/text', (req, res) => {
  res.type('text/plain').send('this is a test');
});

app.use((err, req, res, next) => {
  res.status(500).render('您的访问被不被允许！！');
});

app.use((req, res) => {
  res.status(404).render('你的请求飞到外太空了！');
});

app.post('/login',(req,res)=>{
  if(req.body.user ...){ //数据库比对成功
  res.redirect(200,'/admin')
  } else {
  res.render({login:false,message:'账号与密码不匹配'});
  }
  });