JAVASCRIPT

xmlhttp js post request

var xhr = new XMLHttpRequest();
xhr.open("POST", '/url', true);
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

xhr.onreadystatechange = function() { // Call a function when the state changes.
    if (this.readyState === XMLHttpRequest.DONE && this.status === 200) {
        // Request finished. Do processing here.
    }
}
xhr.send("name=Hello&id=world");

JavaScript POST request with XMLHttpRequest object

let xhr = new XMLHttpRequest();
xhr.open("POST", "https://reqbin.com/echo/post/json");
xhr.setRequestHeader("Accept", "application/json");
xhr.setRequestHeader("Content-Type", "application/json");

xhr.onreadystatechange = function () {
  if (xhr.readyState === 4) {
    console.log(xhr.status);
    console.log(xhr.responseText);
  }};

let data = `{
  "Id": 78912,
  "Customer": "Jason Sweet",
  "Quantity": 1,
  "Price": 18.00
}`;

xhr.send(data);