What is meaning of xhr.readystate===4

Question

Is it right to say that the AJAX call has completed after xhr.readystate===4?
Here it says the state is complete. So what does th

Answer 1

Yes, it is correct.xhr.readstate===4 means request finished and response is ready. You can refer this for details.

Here is small example:

xmlhttp.open("GET", "test.txt", true);
 xmlhttp.onreadystatechange = function() {
     if(xmlhttp.readyState==4) {
         alert(xmlhttp.responseText);
     }
 }
 xmlhttp.send(null);

The above script makes a GET request for the relative url "text.txt" (relative to the calling page) It provides the function, which checks the readyState property each time it's called and when it has the value 4 - meaning the load is complete, it displays the responseText to the user with an alert.

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