f5

        var time = new Date().getTime(); var f5=false; function disableF5(e) { var code = e.which || e.keyCode; if (code == 116){ if(f5){ e.preventDefault(); return false; } var time1 = new Date().getTime(); if(time1 - time < 2000){ e.preventDefault(); return false; } f5=true; } }; document.addEventListener("keydown", disableF5); document.addEventListener("unload", disableF5);