function click(e) {
if (document.all) {
if (event.button==2||event.button==3) { alert("欢迎光临寒舍，有什么需要帮忙的话，请与站长联系！谢谢您的合作！！！");
oncontextmenu='return false';
}
}
if (document.layers) {
if (e.which == 3) {
oncontextmenu='return false';
}
}
}
if (document.layers) {
document.captureEvents(Event.MOUSEDOWN);
}
document.onmousedown=click;
document.oncontextmenu = new Function("return false;")

document.onkeydown =document.onkeyup = document.onkeypress=function(){
if(window.event.keyCode == 123) {
window.event.returnValue=false;
return(false);
}
}
<--123——112是F1-F12的代码数-->