// JScript 文件

/*

参数说明: 
demo 字幕区域标签(div)的ID; 
demo1/demo2 显示内容标签(div或td)的ID demo1为原始内容,demo2是它的拷贝; 
direction 字幕方向(up,down,left,right) ; 
delay 字幕播放的延迟时间(毫秒); 
step 字幕播放的步长(即pix,步长越小,如step=1,滚动越平滑) 

*/


function Marquee (demo, demo1, demo2, direction, delay, step) 
{ 
direction = direction.toLowerCase(); 
if(((direction == "up" || direction == "down") && ($(demo1).offsetHeight > $(demo).offsetHeight)) || ((direction == "left" || direction == "right") && ($(demo1).offsetWidth > $(demo).offsetWidth))) 
{ 
$(demo2).innerHTML = $(demo1).innerHTML; 
if(direction == "down") 
$(demo).scrollTop = 2 * $(demo1).offsetHeight - $(demo).offsetHeight; 
if(direction == "right") 
$(demo).scrollLeft = 2 * $(demo1).offsetWidth - $(demo).offsetWidth; 
} 
else 
return; 
var flag = true; 
var speed = delay == null? 1 : parseInt(delay); 
var amount = step == null? 1 : parseInt(step); 
var Marquee = function () 
{ 
switch(direction) 
{ 
case "up": 
if($(demo2).offsetTop - $(demo).scrollTop <= 0) 
$(demo).scrollTop -= $(demo1).offsetHeight; 
else 
$(demo).scrollTop += amount; 
break; 
case "down": 
if($(demo1).offsetTop - $(demo).scrollTop >= 0) 
$(demo).scrollTop += $(demo2).offsetHeight; 
else 
$(demo).scrollTop -= amount; 
break; 
case "left": 
if($(demo2).offsetWidth - $(demo).scrollLeft <= 0) 
$(demo).scrollLeft -= $(demo1).offsetWidth; 
else 
$(demo).scrollLeft += amount; 
break; 
case "right": 
if($(demo).scrollLeft <= 0) 
$(demo).scrollLeft += $(demo2).offsetWidth; 
else 
$(demo).scrollLeft -= amount; 
break; 
default:break; 
} 
} 
var timer = setInterval(Marquee,speed); 
var play = function () 
{ 
if(flag) 
{ 
clearInterval(timer); 
timer = setInterval(Marquee, speed); 
} 
} 
$(demo).onmouseover = function () 
{ 
if(flag) 
clearInterval(timer); 
} 
$(demo).onmouseout = function () 
{ 
if(flag) 
timer = setInterval(Marquee, speed); 
} 
this.delay = function (s) 
{ 
speed = s == null? 50 : parseInt(s); 
play(); 
} 
this.step = function (s) 
{ 
amount = s == null? 1 : parseInt(s); 
play(); 
} 
this.start = function () 
{ 
if(!flag) 
{ 
flag = true; 
play(); 
} 
} 
this.stop = function () 
{ 
if(flag) 
{ 
flag = false; 
clearInterval(timer); 
} 
} 
this.direction = function (s) 
{ 
s = s.toLowerCase(); 
if( s == direction ) 
return; 
if(s == "down" && direction == "up" ) 
direction = s; 
if(s == "up" && direction == "down") 
direction = s; 
if(s == "right" && direction == "left") 
direction = s; 
if(s == "left" && direction == "right") 
direction = s; 
if (s == direction) 
play(); 
} 
} 


//上面js里用到的$或$F,如果你用过prototype.js的话,把它添加进去就行了; 否则你需要先引用下面的js文件: Ruby.js (从prototype.js里截过来的 呵呵) 


function Ruby () 
{ 
} 
if (!Array.prototype.push) { 
Array.prototype.push = function() { 
var startLength = this.length; 
for (var i = 0; i < arguments.length; i++) 
this[startLength + i] = arguments[i]; 
return this.length; 
} 
} 
$ = function () 
{ 
var elements = new Array(); 
for (var i = 0; i < arguments.length; i++) { 
var element = arguments[i]; 
if (typeof element == "string") 
    element = document.getElementById(element); 
if (arguments.length == 1) 
return element; 
elements.push(element); 
} 
return elements; 
} 
$F = function () 
{ 
if(arguments.length == 1) 
return document.getElementById(arguments[0]).value; 
else 
{ 
var elements = new Array(); 
for(var i = 0;i< arguments.length; i++) 
{ 
elements.push(document.getElementById(arguments[i]).value); 
} 
return elements; 
} 
}