有没有办法将client.js文件中的变量发送到node.js文件？

Question

I am trying to pass in a product number from my client to my server so I can save it to a database. I've tried almost 100 different ways to print out the "prod" variable but nothing is working.

I already have body-parser and other things included in my code. Is there some small thing I'm doing wrong? if so how should I edit my client file or server file to be able to pass in "prod" from the client to server.

As of right now if just says undefined

Client.js:

    function addToCart(prod1) { 
     fetch( '/addToCart' , { method: ' POST ', body: ' prod= ' + prod1 }); 
    }

server.js:

    app.post("/addToCart", (req, res) => {
      console.log(req.body.prod);
    });

I expect whatever "prod" is, to be visible in my server file file when I console.log it out to the screen

Answer 1

Add application/json as header's content type and use JSON.stringify({yourKey:yourData}) as the body.

Client:

function addToCart(prod1) { 
 fetch( '/addToCart' , { 
   headers: { "Content-Type": "application/json" },
   method: ' POST ',
   body: JSON.stringify({prod : prod1 })
 }); 
}

Server:

app.post("/addToCart", (req, res) => {
  console.log(req.body.prod);
});

Answer 2

Why you don't try to send a json object instead a string?

data = {
  prod: prod1
}

function addToCart(data) { 

 fetch( '/addToCart' , { method: ' POST ', body: JSON.stringify(data) }); 

}

Answer 3

The first problem I see here is that you donpt shot the content-type of your client request. If you use for example

headers: { 'Content-Type': 'application/json' }

than the correct way to pass POST data is:

body: JSON.stringify({prod: prod1})