Silverlight 4: Detect browser F5 / refresh and X / Close

Question

I want to determine how to filter F5, refresh button, X and close in browser via silverlight 4.0 or even in server side.

thank you

EDITED:

Answer 1

since it is not possible in client side, i did it in server side.

I solve my problem using this code:

window.onunload = function (e) {
        // Firefox || IE
        e = e || window.event;
        var y = e.pageY || e.clientY;

        if (y < 0) {
            alert("close");
        }
        else {
            alert("refresh");
        }
    }