notify user when wifi, or 3g 4g network get lost jquery or javascript

we have web site which is optimized for mobile phone. we do qute frequent ajax requestes and some time an event get rigered from a back end.

now the problem is how to properly manage when network connection get lost.

can we create a custom event where it will be triggered when a connection get lo开发者_如何学运维st using jquery?

Try this:

function doIhaveInterWebs(){
  $.ajax({
    url: "test.txt",
    success: function() {return true}
    error: function(){return false}
   });
 }

use following code.

$(document).ready(function () {
   if (!Sys.WebForms.PageRequestManager.getInstance().get_isInAsyncPostBack()) {
                Sys.WebForms.PageRequestManager.getInstance().add_endRequest(endRequestHandler);
   }
});

    function endRequestHandler(sender, args) {
        if (args.get_error() != undefined) {
            var errorMessage;
            if (args.get_response().get_statusCode() == '200') {
                errorMessage = args.get_error().message;
            }
            else {
                // Error occurred somewhere other than the server page.
                errorMessage = "Error Message";
            }
            args.set_errorHandled(true);
            $get('ErrorMessage').innerHTML = errorMessage;
        } else {
            // no error occur
        }
    }