<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>IT知道网</title>
    <SCRIPT language=JavaScript>... 
<!--  function CLASS_MSN_MESSAGE(id,width,height,caption,title,message,target,action)...{ 
    this.id     = id; 
    this.title  = title; 
    this.caption= caption; 
    this.message= message; 
    this.target = target; 
    this.action = action; 
    this.width    = width?width:200; 
    this.height = height?height:120; 
    this.timeout= 150; 
    this.speed    = 20;
    this.step    = 1;
    this.right    = screen.width -1; 
    this.bottom = screen.height;
    this.left    = this.right - this.width;
    this.top    = this.bottom - this.height;
    this.timer    = 0;
    this.pause    = false;
    this.close    = false;
    this.autoHide    = true;
} 
 
/**//**//**//* 
*    隐藏消息方法 
*/ 
CLASS_MSN_MESSAGE.prototype.hide = function()...{ 
    if(this.onunload())...{ 

        var offset  = this.height>this.bottom-this.top?this.height:this.bottom-this.top;
        var me  = this; 

        if(this.timer>0)...{  
            window.clearInterval(me.timer); 
        } 

        var fun = function()...{ 
            if(me.pause==false||me.close)...{
                var x  = me.left;
                var y  = 0;
                var width = me.width;
                var height = 0;
                if(me.offset>0)...{
                    height = me.offset;
                }
    
                y  = me.bottom - height;
    
                if(y>=me.bottom)...{
                    window.clearInterval(me.timer); 
                    me.Pop.hide(); 
                } else ...{
                    me.offset = me.offset - me.step; 
                }
                me.Pop.show(x,y,width,height);   
            }            
        } 

        this.timer = window.setInterval(fun,this.speed)     
    } 
} 
 
/**//**//**//* 
*    消息卸载事件，可以重写 
*/ 
CLASS_MSN_MESSAGE.prototype.onunload = function() ...{ 
    return true; 
} 
/**//**//**//* 
*    消息命令事件，要实现自己的连接，请重写它 
* 
*/ 
CLASS_MSN_MESSAGE.prototype.oncommand = function()...{ 
    //this.close = true;
    this.hide(); 
    window.open("Default4.aspx");
  
}
/**//**//**//* 
*    消息显示方法 
*/ 
CLASS_MSN_MESSAGE.prototype.show = function()...{ 

    var oPopup = window.createPopup(); //IE5.5+ 
   
    this.Pop = oPopup; 
 
    var w = this.width; 
    var h = this.height; 
 
    var str = "<DIV style='BORDER-RIGHT: #455690 1px solid; BORDER-TOP: #a6b4cf 1px solid; Z-INDEX: 99999; LEFT: 0px; BORDER-LEFT: #a6b4cf 1px solid; WIDTH: " + w + "px; BORDER-BOTTOM: #455690 1px solid; POSITION: absolute; TOP: 0px; HEIGHT: " + h + "px; BACKGROUND-COLOR: #c9d3f3'>" 
        str += "<TABLE style='BORDER-TOP: #ffffff 1px solid; BORDER-LEFT: #ffffff 1px solid' cellSpacing=0 cellPadding=0 width='100%' bgColor=#cfdef4 border=0>" 
        str += "<TR>" 
        str += "<TD style='FONT-SIZE: 12px;COLOR: #0f2c8c' width=30 height=24></TD>" 
        str += "<TD style='PADDING-LEFT: 4px; FONT-WEIGHT: normal; FONT-SIZE: 12px; COLOR: #1f336b; PADDING-TOP: 4px' valign=middle width='100%'>" + this.caption + "</TD>" 
        str += "<TD style='PADDING-RIGHT: 2px; PADDING-TOP: 2px' valign=middle align=right width=19>" 
        str += "<SPAN title=关闭 style='FONT-WEIGHT: bold; FONT-SIZE: 12px; CURSOR: hand; COLOR: red; MARGIN-RIGHT: 4px' id='btSysClose' >×</SPAN></TD>" 
        str += "</TR>" 
        str += "<TR>" 
        str += "<TD style='PADDING-RIGHT: 1px;PADDING-BOTTOM: 1px' colSpan=3 height=" + (h-28) + ">" 
        str += "<DIV style='BORDER-RIGHT: #b9c9ef 1px solid; PADDING-RIGHT: 8px; BORDER-TOP: #728eb8 1px solid; PADDING-LEFT: 8px; FONT-SIZE: 12px; PADDING-BOTTOM: 8px; BORDER-LEFT: #728eb8 1px solid; WIDTH: 100%; COLOR: #1f336b; PADDING-TOP: 8px; BORDER-BOTTOM: #b9c9ef 1px solid; HEIGHT: 100%'>" + this.title + "<BR><BR>" 
        str += "<DIV style='WORD-BREAK: break-all' align=left><A href='javascript:void(0)' hidefocus=false id='btCommand'><FONT color=#ff0000>" + this.message + "</FONT></A>fghfghfghghghgh<A href='' hidefocus=false id='ommand'><FONT color=#ff0000>这里的信息是你要显示的，你可以把它链接改成你的链接，就是一点可以去哪页 的功能，因为用户登录后会有一个session的ID，所以这里你只要给一个页面连接，到这个页面里再用session的ID来进行选择相应的消息 就可以了。</FONT></A></DIV>" 
        str += "</DIV>" 
        str += "</TD>" 
        str += "</TR>" 
        str += "</TABLE>" 
        str += "</DIV>" 
 
    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=false;}

    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.top)...{
            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)     
 
    
 
    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",200,120,"短消息提示：","您有1封消息",""); 
    MSG1.rect(null,null,null,screen.height-50);
    MSG1.speed    = 10;
    MSG1.step    = 5;
    //alert(MSG1.top);
    var i = <%=i%>;
    if(i==1)//这里是做一个判断用来判断用户是否有新的消息
    ...{
        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(); 
//--> 
</SCRIPT>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        &nbsp;&nbsp;
   
    </div>
    </form>
</body>
</html>
 这是前台页面。
后台页面就简单多了，我只是做了一个简单的判断。没有做数据库的链接判断。 public static int i = 0;//这里定义一个静态变量用来存储状态值的。因为做为静态处理，你在前台页面可以使用它。

    protected void Page_Load(object sender, EventArgs e)
    ...{
        i = 2;
    }好了，看一下效果吧。应该还是不错的。