求判断窗口最大化的代码


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function addbook(){
alert("IE only")}
var mode=0
var old=new Array();
function fullme(e){
if(mode==0){
if(typeof document.all!='undefined'){
if(top.document.body.offsetWidth==screen.availWidth){
alert("信息提示：你的浏览器已被锁定视窗最大化，无法启用全屏模式！");
e.returnValue=false;
return false;
}
top.moveBy(e.clientX-e.screenX,e.clientY-e.screenY);
top.resizeBy(screen.availWidth-top.document.body.offsetWidth,
screen.availHeight-top.document.body.offsetHeight);
}else{
window.top.moveTo(0,0);
window.top.resizeTo(screen.availWidth,screen.availHeight);
old[0]=window.toolbar.visible;
old[1]=window.statusbar.visible;
old[2]=window.menubar.visible;
window.toolbar.visible=false;
window.statusbar.visible=false;
window.menubar.visible=false;
}
mode=1;
}else{
if(typeof document.all!='undefined'){
top.moveTo(0,0);
top.resizeTo(screen.availWidth,screen.availHeight);
}else{
window.toolbar.visible=old[0];
window.statusbar.visible=old[1];
window.menubar.visible=old[2];
}
mode=0;
}
return true;
}
--></SCRIPT>
<body scroll=no onload=fullme(event)>