无法使用 Mongoose 从数据库中删除项目

Question

我试图在博客网站中添加此删除功能，这样当用户单击删除按钮时，它会从数据库中删除该特定项目，但我遇到了一些错误。

这是我的家.ejs：

 <%- include("partials/header"); -%>
    <h1>Home</h1>
    <p> <%= startingContent %> </p>


  <%  posts.forEach(function(post){ %>

    <h1><%=post.title%></h1>
    <p>
    <%=post.content.substring(0, 100) + " ..."%>
    <a href="/posts/<%=post._id%>">Read More</a>
    </p>


    <% }) %>

<%- include("partials/footer"); -%>

这是 post.ejs（每个日记条目的页面，当有人点击阅读更多时，它会将用户发送到该特定帖子的页面）

<%- include("partials/header"); -%>

  <h1><%=title%></h1>
  <p><%=content%></p>

  <form action="/posts/delete" method="post">
    <button class="btn btn-warning btn-small" name="button" type="submit" value="<%=post._id%>">Delete</button>
  </form>

<%- include("partials/footer"); -%>

这是我的 app.js：

//jshint esversion:6

const express = require("express");
const bodyParser = require("body-parser");
const ejs = require("ejs");
const mongoose = require("mongoose");

const homeStartingContent = "Lacus vel facilisis volutpat est velit egestas dui id ornare. Semper auctor neque vitae tempus quam. Sit amet cursus sit amet dictum sit amet justo. Viverra tellus in hac habitasse. Imperdiet proin fermentum leo vel orci porta. Donec ultrices tincidunt arcu non sodales neque sodales ut. Mattis molestie a iaculis at erat pellentesque adipiscing. Magnis dis parturient montes nascetur ridiculus mus mauris vitae ultricies. Adipiscing elit ut aliquam purus sit amet luctus venenatis lectus. Ultrices vitae auctor eu augue ut lectus arcu bibendum at. Odio euismod lacinia at quis risus sed vulputate odio ut. Cursus mattis molestie a iaculis at erat pellentesque adipiscing.";
const aboutContent = "Hac habitasse platea dictumst vestibulum rhoncus est pellentesque. Dictumst vestibulum rhoncus est pellentesque elit ullamcorper. Non diam phasellus vestibulum lorem sed. Platea dictumst quisque sagittis purus sit. Egestas sed sed risus pretium quam vulputate dignissim suspendisse. Mauris in aliquam sem fringilla. Semper risus in hendrerit gravida rutrum quisque non tellus orci. Amet massa vitae tortor condimentum lacinia quis vel eros. Enim ut tellus elementum sagittis vitae. Mauris ultrices eros in cursus turpis massa tincidunt dui.";
const contactContent = "Scelerisque eleifend donec pretium vulputate sapien. Rhoncus urna neque viverra justo nec ultrices. Arcu dui vivamus arcu felis bibendum. Consectetur adipiscing elit duis tristique. Risus viverra adipiscing at in tellus integer feugiat. Sapien nec sagittis aliquam malesuada bibendum arcu vitae. Consequat interdum varius sit amet mattis. Iaculis nunc sed augue lacus. Interdum posuere lorem ipsum dolor sit amet consectetur adipiscing elit. Pulvinar elementum integer enim neque. Ultrices gravida dictum fusce ut placerat orci nulla. Mauris in aliquam sem fringilla ut morbi tincidunt. Tortor posuere ac ut consequat semper viverra nam libero.";

const app = express();

app.set('view engine', 'ejs');

app.use(bodyParser.urlencoded({extended: true}));
app.use(express.static("public"));
mongoose.set('useNewUrlParser', true);
mongoose.set('useUnifiedTopology', true);

mongoose.connect("mongodb://localhost:27017/blogDB");

const postSchema = {
  title: String,
  content: String
};

const Post = mongoose.model("Post", postSchema);

app.get("/", function(req, res){

  Post.find({}, function(err, posts) {
    res.render("home", {
      startingContent: homeStartingContent,
      posts: posts
      });
  });

});

app.get("/about", function(req, res){
  res.render("about", {aboutContent: aboutContent});
});

app.get("/contact", function(req, res){
  res.render("contact", {contactContent: contactContent});
});

app.get("/compose", function(req, res){
  res.render("compose");
});

app.post("/compose", function(req, res){
  const post = new Post ({
    title: req.body.postTitle,
    content: req.body.postBody
  });

  post.save(function(err){

   if (!err){
     res.redirect("/");
   }

  });

});

app.get("/posts/:postId", function(req, res){
  const requestedPostId = req.params.postId;

  Post.findOne({_id: requestedPostId}, function(err, post) {
    res.render("post", {
      title: post.title,
      content: post.content
    });
  });

});

app.post("/delete", function (req, res) {
  const idDelete = req.body.button;

  Post.findByIdAndRemove(idDelete, function(err) {
    if (!err) {
      console.log("Deleted Sucessfully");
    }
    res.redirect("/");
  });
});

app.listen(3000, function() {
  console.log("Server started on port 3000");
});

但我遇到的问题是，服务器拒绝识别我在 post.ejs 中用于按钮值的“post._id”。

如果我删除按钮值，控制台日志会显示“已成功删除”，我也会被重定向到主页，但它根本不会删除帖子。

这就是我的帖子页面的外观（但正如我所说，它真的不起作用，如果我点击删除，我只会被重定向到主页：

Answer 1

在渲染post.ejs 时需要传递_id 或完成post 对象。你只是传递了title 和content。