JS实现定时页面弹出类似QQ新闻的提示框_javascript技巧

还是在做联通IOM项目时遇到的一个需求,要求页面每隔半小时弹出一次提示消息（消息以类似QQ新闻的形式弹出）。当时上网找的这么一个资料，已经不记得原文出处了

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str += ""
str += ""
str += ""
str += ""
str += ""
str += ""
str += ""
str += ""
str += ""
str += ""

oPopup.document.body.innerHTML = str;
this.offset = 0;
var me = this;

oPopup.document.body.onmouseover = function(){me.pause=true;}
oPopup.document.body.onmouseout = function(){me.pause=true;}

var fun = function(){
var x = me.left;
var y = 0;
var width = me.width;
var height = me.height;

if(me.offset>me.height){
height = me.height;
} else {
height = me.offset;
}

y = me.bottom - me.offset;
if(y//me.timeout--;
if(me.timeout==0){
window.clearInterval(me.timer);
if(me.autoHide){
me.hide();
}
}
} else {
me.offset = me.offset + me.step;
}
me.Pop.show(x,y,width,height);
}

this.timer = window.setInterval(fun,this.speed)

//"确认"关闭事件

var buttonClose = oPopup.document.getElementById("buttonClose");
buttonClose.onclick = function(){
me.close = true;
me.hide();
}
/*
* "×"关闭事件
* var btClose = oPopup.document.getElementById("btSysClose");
*
* btClose.onclick = function(){
* me.close = true;
* me.hide();
* }
*/

var btCommand = oPopup.document.getElementById("btCommand");
btCommand.onclick = function(){
me.oncommand();
}
var ommand = oPopup.document.getElementById("ommand");
ommand.onclick = function(){
this.close = true;
me.hide();
window.open(ommand.href);
}
}
/*
* 设置速度方法
*/
CLASS_MSN_MESSAGE.prototype.speed = function(s){
var t = 20;
try {
t = praseInt(s);
} catch(e){}
this.speed = t;
}
/**
* 设置步长方法
*/
CLASS_MSN_MESSAGE.prototype.step = function(s){
var t = 1;
try {
t = praseInt(s);
} catch(e){}
this.step = t;
}

CLASS_MSN_MESSAGE.prototype.rect = function(left,right,top,bottom){
try {
this.left = left !=null?left:this.right-this.width;
this.right = right !=null?right:this.left +this.width;
this.bottom = bottom!=null?(bottom>screen.height?screen.height:bottom):screen.height;
this.top = top !=null?top:this.bottom - this.height;
} catch(e){}
}
var MSG1 = new CLASS_MSN_MESSAGE("aa",240,150,"管理员：","思路决定出路","迷失路上");
MSG1.rect(null,null,null,screen.height-50);
MSG1.speed = 10;
MSG1.step = 5;
//alert(MSG1.top);
//MSG1.show();
//同时两个有闪烁，只能用层代替了，不过层不跨框架
/*
var MSG2 = new CLASS_MSN_MESSAGE("aa",200,120,"短消息提示：","您有2封消息","好的啊");
MSG2.rect(100,null,null,screen.height);
MSG2.show();
*/

/**
* 显示提示框
*/
function showMSG(){
MSG1.show();
}

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