Uncaught Error: INVALID_STATE_ERR: DOM Exception 11

Question

I am getting the below error.

Uncaught Error: INVALID_STATE_ERR: DOM Exception 11

Here is the code where I am getting Error RUN TIME.

xhttp.setRequestHeader("Content-type","application/xhtml+xml");<br>
xhttp.open("POST",xmlFile,true);<br>
xhttp.send(postData);

I tried with false in the third parameter of xhttp.open.
Can anyone tell me what's causing this?

Answer 1

The error comes from the order of execution:

xhttp.open("POST",xmlFile,true);
xhttp.setRequestHeader("Content-type","application/xhtml+xml");
xhttp.send(postData);

You must first open the connection and then set the request header otherwise you will get the error.

Answer 2

The XMLHttpRequest::Status is unavailable till the XMLHttpRequest::readyState has changed to 4 ie. a proper response has been acquired from the server and has now been populated in the Status variable.

Thus accessing the XMLHttpRequest::Status early can result in this error.

Solution: first verify readyState and only upon success — access Status

if (xmlhttp.readyState==4)
{
    switch (xmlhttp.status)
    {
    case 200: // Do the Do
        break;
    case 404: // Error: 404 - Resource not found!
        break;
    default:  // Error: Unknown!
    }
}