How many times onreadystatechange property of XMLHTTPREQUEST would be get called?

[Ravi Kiran Va]

The following below code is related to AJAX .

can anybody please let me know how many times the function getOutput will be getting called ??

function loadContent()
{

    var url="loadJSP.jsp";
    xmlhttp.onreadystatechange=getOutput;
    xmlhttp.open("GET",url,true);
    xmlhttp.send(null);
}

function getOutput()
{
  if (xmlhttp.readyState==4)
  {
  document.getElementById("prtCnt").innerHTML=xmlhttp.responseText;
  }
}

Waiitng for your replies .
Thanks in advance .

[Ankit Garg]

A very simple google search would've landed you here...

[Ankit Garg]

Moving to Html/Javascript forum...

[Saifuddin Merchant]

W3schools offers a better explanation on the ready-state-change here.

To answer your question in particular, it cannot be determined. While transitions between states are defined certain states may trigger the on-ready-state function multiple times (e.g. 3: processing request ).

Note - W3schools mentions that "onreadystatechange event is triggered four times, one time for each change in readyState.", but I remember of some place that onreadystatechange could trigger of multiple times, for the same state.

Usually there is no interest in the other states and the only state that is important is readyState==4 and status==200. Using a Javascript library JQuery, Prototype even hide this and give you simple function to work with like Ajax.Load('page', element)

[vijin das]

The onreadystatechange event is triggered every time the readyState changes.

The readyState property holds the status of the XMLHttpRequest and Changes from 0 to 4:

The onreadystatechange event is triggered four times, one time for each change in readyState and which are like ...


0: request not initialized
1: server connection established
2: request received
3: processing request
4: request finished and response is ready

In the onreadystatechange event, we specify what will happen when the server response is ready to be processed.

When readyState is 4 and status is 200, the response is ready:

[Ravi Kiran Va]

Thank you very much .

Javaranch has helped me a lot , how can i help this site in back ??