how to define xmlhttprequest in javascript code example

Example 1: xmlhttprequest javascript

function reqListener () {
  console.log(this.responseText);
}

var oReq = new XMLHttpRequest();
oReq.onload = reqListener;
oReq.open("GET", "http://www.example.org/example.txt");
oReq.send();

Example 2: javascript howto get xhr

function httpGet(theUrl)
{
    var xmlHttp = new XMLHttpRequest();
    xmlHttp.open( "GET", theUrl, false ); // false for synchronous request
    xmlHttp.send( null );
    return xmlHttp.responseText;
}