app.post('/admin/movie/new',function(req,res){
  var id = req.body.movie._id
  console.log('提交:'+id)

  var movieObj = req.body.movie
  var _movie

  if (id !== 'undefined') {
    Movie.findById(id,function(err,movie){
      if (err) {
        console.log(err)
      }

      _movie = _.extend(movie,movieObj)
      _movie.save(function(err,movie){
        if (err) {
          console.log(err)
        }

        res.redirect('/movie/'+movie._id)
      })
    })
  }

和

   form.form-horizontal(method="post",action="/admin/movie/new")
             input(type="hidden",name="movie[_id]",value="#{movie._id}")