Javascript实现的类似Google的Div拖动效果代码_javascript技巧

JScript 文件：
//检测浏览器 MSIE Firefox
var ie=false,moz=false;
(function()
{//check the browser
var userAgent=navigator.userAgent;
if(userAgent.indexOf("MSIE")!=-1)
ie=true;
else if(userAgent.indexOf("Firefox")!=-1)
moz=true;
})();
//通过ID获得对象
function $E_ID(idString)
{
return document.getElementById(idString);
}
//通过Name获得对象
function $Es_Tag(tagName)
{
return document.getElementsByTagName(tagName);
}
//获得对象绝对位置 obj.offsetparent
function $GetInfo(o)
{
var to=new Object();
to.left=to.right=to.top=to.bottom=0;
var twidth=o.offsetWidth;
var theight=o.offsetHeight;
while(o)
{
to.left+=o.offsetLeft;
to.top+=o.offsetTop;
o=o.offsetParent;
}
to.right=to.left+twidth;
to.bottom=to.top+theight;
return to;
}
//鼠标点击对象确发事件
function $hitTest(obj,event)
{
obj=$GetInfo(obj);
var x=event.clientX;
var y=event.clientY;
if((x>=obj.left&&x<=obj.right)&&(y>=obj.top&&y<=obj.bottom))
　return true;
else
　return false;
}
function Drag(event)
{
this.dragged=false;
this.ao=null;
this.tdiv=null;
this.fixLeft=0;
this.fixTop=0;
this.lastX=event.clientX;
this.lastY=event.clientY;
Drag.mm=null;
this.dragStart=function(event)
{
this.ao=ie?event.srcElement:(moz?event.target:null);
if(ie)
document.body.onselectstart=function()
{
　　return false
　　}
if(moz&&this.ao.nodeType==3)
　this.ao=this.ao.parentNode;
if(this.ao.tagName=="TD"||this.ao.tagName=="TR")
　this.ao=this.ao.offsetParent.parentNode;
else
　return;
if(this.ao.className!="dragdiv")
　return;
this.tdiv=$E_ID("tmpdiv");
this.tdiv.style.visibility="visible";
this.tdiv.style.filter="alpha(opacity=70)";
if(ie)
　this.tdiv.filters.alpha.opacity=70;
this.tdiv.style.opacity=0.7;
this.tdiv.style.zIndex=100;
this.tdiv.innerHTML=this.ao.innerHTML;
this.tdiv.style.width=this.ao.offsetWidth+"px";
this.tdiv.style.height=this.ao.offsetHeight+"px";
this.tdiv.style.top=$GetInfo(this.ao).top+"px";
this.tdiv.style.left=$GetInfo(this.ao).left+"px";
this.fixTop=parseInt($GetInfo(this.tdiv).top);
this.fixLeft=parseInt($GetInfo(this.tdiv).left);
this.dragged=true;
}
this.onDrag=function(event)
{
if((!this.dragged)||this.ao==null)return;
var tX=event.clientX;
var tY=event.clientY;
this.tdiv.style.left=parseInt(this.fixLeft+tX-this.lastX-document.body.scrollLeft)+"px";
this.tdiv.style.top=parseInt(this.fixTop+tY-this.lastY-document.body.scrollTop)+"px";
for(var m=0;m<$E_ID("root").rows.length;m++)
{
var rootCells=$E_ID("root").rows[m].cells;
for(var i=0;i<rootCells.length;i++)
{
if($hitTest(rootCells[i],event))
{
if(rootCells[i].hasChildNodes())
{
for(var j=0;j<rootCells[i].childNodes.length;j++)
{
if($hitTest(rootCells[i].childNodes[j],event))
{
rootCells[i].insertBefore(this.ao,rootCells[i].childNodes[j]);
break;
}
}
if(j==rootCells[i].childNodes.length)
{
rootCells[i].appendChild(this.ao);break;
}
break;
}
else
{
rootCells[i].appendChild(this.ao);
break;
}
}
}
}
}
this.dragEnd=function()
{
if(this.dragged)
{
this.dragged=false;
Drag.mm=this.repos(150,15,this);
this.ao=null;
}
if(ie)document.body.onselectstart=function(){return true}
}
this.repos=function(aa,ab,obj)
{
if(ie)var f=obj.tdiv.filters.alpha.opacity;
else if(moz)var f=obj.tdiv.style.opacity*100;
var kf=f/ab;
var tl=parseInt($GetInfo(obj.tdiv).left);
var tt=parseInt($GetInfo(obj.tdiv).top);
var kl=(tl-$GetInfo(obj.ao).left)/ab;
var kt=(tt-$GetInfo(obj.ao).top)/ab;
return setInterval(function(){
if(ab<1)
{
clearInterval(Drag.mm);
obj.tdiv.style.visibility="hidden";
obj.tdiv.style.zIndex="";
return;
}
ab--;
tl-=kl;
tt-=kt;
f-=kf;
obj.tdiv.style.left=parseInt(tl)+"px";
obj.tdiv.style.top=parseInt(tt)+"px";
if(ie)obj.tdiv.filters.alpha.opacity=f;
else if(moz)obj.tdiv.style.opacity=f/100;
},aa/ab );
}
}
var tDrag=null;
function init(event)
{
// alert(event.target.innerHTML);
tDrag=new Drag(event);
tDrag.dragStart(event);
}
function move(event)
{
if(tDrag!=null)tDrag.onDrag(event);
}
function end()
{
if(tDrag!=null){
tDrag.dragEnd();
tDrag=null;
}
}
Asp.net文件：
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>