Author: abhijit

I always struggle with understanding how async / await works.

So, I decided to write the code down and refer to this rather than trying to think it though every time!

I’ll start with the simple XMLHttpRequest

var req = new XMLHttpRequest();

req.onreadystatechange = function () {

  req.onload = function () {
    if (req.status == 200) {
      console.info('success')
      var arr = JSON.parse(req.responseText);
      populatePage(arr);
    }
    else {
      console.info('error')
    }
  }
}

req.open('GET', baseURL, true);
req.send();

Here, I’m hitting baseURL (defined outside of this code) and doing something with the received array with the populatePage function outside as well.

I wrote it like this so that I don’t add other code which is not relevant to the call.