The readyState property indicates the current state of the request. It returns a
This property is read-only and has the following defined values
The object has been created, but has not been initialized (the
open method has not been called).
The object has been created but the send
method has not been called.
The send method has been called and the status
and headers are available, but the response is not.
some data has been received. You can get the partial results using the
responseBody and the
All the data has been received, and is available.
This property is a Microsoft extension to the W3C DOM.