js禁止页面回退,刷新,右键代码

//禁止页面回退
javascript: window.history.forward(1);
//禁止页面刷新
document.onkeydown = function() {
if ((event.keyCode == 116) || (event.ctrlKey && event.keyCode == 82))
 {
 event.keyCode = 0;
 event.returnValue = false;
 }
}

//js屏蔽浏览器（IE和FireFox）的刷新功能
document.onkeydown=function(){
if ((window.event.keyCode==116)|| //屏蔽 F5(window.event.keyCode==122)|| //屏蔽 F11(window.event.shiftKey && window.event.keyCode==121)
//shift+F10)
{
window.event.keyCode=0;
window.event.returnValue=false;
}if ((window.event.altKey)&&(window.event.keyCode==115))
{
//屏蔽Alt+F4
window.showModelessDialog("about:blank","","dialogWidth:1px;dialogheight:1px");
return false;
}
}
//js屏蔽右键
if (window.Event)document.captureEvents(Event.MOUSEUP);
function nocontextmenu(){
event.cancelBubble = trueevent.returnValue = false;return false;
}function norightclick(e){
if (window.Event){
if (e.which == 2 || e.which == 3)return false;
}else if (event.button == 2 || event.button == 3){
event.cancelBubble = true   event.returnValue = false;
         return false;
}}
document.oncontextmenu = nocontextmenu;
// for IE5+
document.onmousedown = norightclick;
// for all others//js屏蔽F5键刷新