How to make a http request in JavaScript

Question

I'm doing a quick exercise about HttpRequest in JavaScript. I want to get data from the localhost. So made a request in client end like below.

  var httpRequest = new XMLHttpRequest();
  httpRequest.open('GET', 'http://localhost:4000/', true);
  httpRequest.send;

  httpRequest.onreadystatechange = function(){
    if(httpRequest.readyState ==4 && httpRequest.status ==200){
      var json = httpRequest.responseText;
      console.log(json)
    }
  }

And the server side

app.get('http://localhost:4000/',(req,res) => {
  res.status(200).send({username: "123"})
})

However, it doesn't work, I can't get the username data in client. How should I MODIFY the code?

`httpRequest.send()` is a method, you need to call it. – Thomas Apr 23 '21 at 10:27 — Thomas, Apr 23 '21 at 10:27

score 0 · Answer 1 · answered Apr 22 '21 at 22:27

0

Look at the introductory documentation for Express.

The route is defined using only the path, not the full URL.

app.get('http://localhost:4000/',(req,res) => {
  res.status(200).send({username: "123"})
})

Note that if you aren't loading the HTML document from your Express server you will have to use CORS to grant permission to read the JSON across origins.

answered Apr 22 '21 at 22:27

Quentin

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Thanks, I changed the route to ' / ', but still got nothing – Jesse Apr 22 '21 at 22:33

How to make a http request in JavaScript

1 Answers1