Javascript Post请求不起作用，错误显示为“；无法发布/addstudent/add"；

这是我想发送的post请求，但它不起作用。我试着在Postman中使用它，也试着使用表单，但错误是“Cannotpost/addstudent/add”。下面是代码

这是JScode：我正在使用express并使用它在MongoDB中发布它

app.post('/addstudent/add', function(req, res){
db.collection('students').insertOne(req.body, function(error, result){
    if(error)
        throw error;
    res.json(result);
    console.log("New student Successfully Added!");
    })
})

这是HTML代码：

<div class="container-fluid">
    <div class="formdiv">
        <form action="/addstudent/add" method="POST"> 
            <div class="form-group">
                <label for="exampleInputEmail1">Student Name</label>
                <input type="text" class="form-control" id="exampleInputEmail1" aria-describedby="emailHelp" placeholder="Enter Name" name="Name">
                <small id="emailHelp" class="form-text text-muted">We'll never share your email with anyone else.</small>
            </div>
            <div class="form-group">
                <label for="exampleInputPassword1">Student Email</label>
                <input type="text" class="form-control" id="exampleInputPassword1" placeholder="Email" name="Email">
            </div>
            <div class="form-group">
                <label for="exampleInputPassword1">Phone Number</label>
                <input type="number" class="form-control" id="exampleInputPassword1" placeholder="Phone Number" name="Number">
            </div>
            <div class="form-group">
                <label for="exampleInputPassword1">Age</label>
                <input type="number" class="form-control" id="exampleInputPassword1" placeholder="Age" name="Age">
            </div>
            <button type="submit" class="btn btn-primary">Submit</button>
        </form>
    </div>
</div>

试试这个

var express = require('express');
var bodyParser = require('body-parser');
var mongoDB = require('mongodb').MongoClient;
var hbs = require('hbs');

const port = process.env.PORT || 3000;
var app = express();
app.use(express.static(__dirname +'/public'));

//Add this line
 app.use( bodyParser.urlencoded({extended:false}));
 app.use(bodyParser.json())

var url = 'mongodb://localhost:27017';
var db;

 mongoDB.connect(url, {useUnifiedTopology: true, useNewUrlParser: true }, 
 function(error, client){
if(error)
    throw error;
db = client.db('attainu');
  });

 app.get('/instructors', function(req, res){
 res.render('instructor.hbs');
})

app.get('/students', function(req, res){
   res.render('index.hbs');
});

app.post('/addstudent/add', function(req, res){
    db.collection('students').insertOne(req.body, function(error, result){
    if(error)
        throw error;
    res.json(result);
    console.log("New student Successfully Added!");
  });
});

app.listen(port, () => console.log(`Server is running at ${port}`));

---

我试着运行上面给出的代码，一切都很好。我没有对代码做任何更改。正在发布数据并成功保存到数据库中。结果如下图所示：

---

显示你的根

js

文件我已经上传了整个js文件你是如何启动你的服务器的？

var express = require('express');
var bodyParser = require('body-parser');
var mongoDB = require('mongodb').MongoClient;
var hbs = require('hbs');

const port = process.env.PORT || 3000;
var app = express();
app.use(express.static(__dirname +'/public'));

//Add this line
 app.use( bodyParser.urlencoded({extended:false}));
 app.use(bodyParser.json())

var url = 'mongodb://localhost:27017';
var db;

 mongoDB.connect(url, {useUnifiedTopology: true, useNewUrlParser: true }, 
 function(error, client){
if(error)
    throw error;
db = client.db('attainu');
  });

 app.get('/instructors', function(req, res){
 res.render('instructor.hbs');
})

app.get('/students', function(req, res){
   res.render('index.hbs');
});

app.post('/addstudent/add', function(req, res){
    db.collection('students').insertOne(req.body, function(error, result){
    if(error)
        throw error;
    res.json(result);
    console.log("New student Successfully Added!");
  });
});

app.listen(port, () => console.log(`Server is running at ${port}`));