ajax docs code example

Example 1: ajax open a request

<script>
function loadDoc() {
  var xhttp = new XMLHttpRequest();
  
  //looking for a change or state , like a request or get.
  xhttp.onreadystatechange = function() {
     
     //if equal to 4 means that its ready.
    // if equal to 200 indicates that the request has succeeded.
    if (this.readyState == 4 && this.status == 200) {
      document.getElementById("demo").innerHTML = this.responseText;
    }
  };
  
  //GET method for gettin the data // the file you are requesting
  xhttp.open("GET", "TheFileYouWant.html", true);
  
  //sending the request
  xhttp.send();
}

Example 2: ajax

With Ajax, web applications can send and retrieve data from a server asynchronously without interfering with the display and behaviour of the existing page.

Example 3: ajax mdn

<button id="ajaxButton" type="button">Make a request</button>

<script>
(function() {
  var httpRequest;
  document.getElementById("ajaxButton").addEventListener('click', makeRequest);

  function makeRequest() {
    httpRequest = new XMLHttpRequest();

    if (!httpRequest) {
      alert('Giving up :( Cannot create an XMLHTTP instance');
      return false;
    }
    httpRequest.onreadystatechange = alertContents;
    httpRequest.open('GET', 'test.html');
    httpRequest.send();
  }

  function alertContents() {
    if (httpRequest.readyState === XMLHttpRequest.DONE) {
      if (httpRequest.status === 200) {
        alert(httpRequest.responseText);
      } else {
        alert('There was a problem with the request.');
      }
    }
  }
})();
</script>