js拖动层

浏览数：41 / 时间：2015年06月09日

模仿网易彩票网（http://caipiao.163.com/）的登陆框自己做了一个拖动层，不过有点小问题——在谷歌浏览拖动的时候鼠标状态变成了文字状态（cursor:text;)

 1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 2 <html xmlns="http://www.w3.org/1999/xhtml">
 3 <head>
 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 5 <title>js拖动层</title>
 6 <style>
 7 body{padding:0; margin:0; width:100%; height:100%;}
 8 * html,* html body{background-image:url(about:blank);background-attachment:fixed}
 9 #dragWp{width:100%; height:100%; position:fixed; left:0; top:0; z-index:99999999; _position:absolute;_left:expression(eval(document.documentElement.scrollLeft));_top:expression(eval(document.documentElement.scrollTop))}
10 #dragBg{ width:100%; height:100%; background-color:#000; position:absolute; left:0; top:0; opacity:0.4; filter:alpha(opacity=40);}
11 #dragMain{width:200px;height:100px;position:absolute; border:1px solid #999;line-height:30px;font-size:16px;text-align:center; background-color:#FFF;}
12 #dragTitle{ width:100%; height:40px; line-height:40px; background-color:#ccc; cursor:move;}    
13 #close{float:right; margin-right:5px; z-index:999; font-size:12px; font-style:normal; cursor:pointer;}
14 </style>    
15 </head>
16 <body>
17 <div style="height:1200px; text-align:center;">
18     <h1>hello world</h1>
19 </div>
20 <div id="dragWp">
21     <div id="dragBg"></div>
22     <div id="dragMain">
23         <div id="dragTitle">
24             <em id="close">关闭</em>拖动层
25         </div>
26         hello world
27     </div>
28 </div>
29 <script>
30 window.onload=function(){
31     var dragWp=document.getElementById("dragWp");
32     var dragMainId=document.getElementById("dragMain");
33     var w=dragWp.offsetWidth;
34     var h=dragWp.offsetHeight;
35     dragMainId.style.left=(w-dragMainId.offsetWidth)/2+"px";
36     dragMainId.style.top=(h-dragMainId.offsetHeight)/2+"px";
37 }
38 
39 function dragTemp(dragWp,dragMainId,dragTitleId,closeId,opacity){
40     var dragWp=document.getElementById(dragWp);
41     var dragMainId=document.getElementById(dragMainId);
42     var dragTitleId=document.getElementById(dragTitleId);
43     var closeId=document.getElementById(closeId);
44     var posX,posY,x,y;
45     dragTitleId.onmousedown=function(e){
46         var e = e || window.event;
47         posX=e.clientX-dragMainId.offsetLeft; //鼠标距离拖动层左侧的距离
48         posY=e.clientY-dragMainId.offsetTop;  //鼠标距离拖动层上侧的距离
49         dragMainId.style.opacity=opacity;
50         dragMainId.style.filter="alpha(opacity="+opacity*100+")";
51         document.onmousemove=function(e){
52             var e = e || window.event;
53             x=e.clientX-posX;
54             y=e.clientY-posY;
55 //            if(x<=0) x=0;    //不允许移出左边
56 //            else if(x>=document.body.clientWidth-dragMainId.offsetWidth) x=document.body.clientWidth-dragMainId.offsetWidth; //不允许移出右边
57             dragMainId.style.left=x+"px";
58             dragMainId.style.top=y+"px";
59             dragTitleId.style.cursor="move";
60             document.onselectstart=function(){ return false } //拖动不选中文字
61         }
62     };
63     document.onmouseup=function(){
64         document.onmousemove=null;
65         dragMainId.style.opacity=1;
66         dragMainId.style.filter="alpha(opacity=100)";
67     }
68     if(closeId){
69         closeId.onclick=function(){
70             dragWp.style.display="none";    
71         }
72     }
73 }
74 function drag(args){
75     dragTemp(args.dragWp,
76              args.dragMainId,
77              args.dragTitleId,
78              args.closeId || null,
79              args.opacity || 1)    
80 }
81 //调用
82 drag({dragWp:"dragWp",dragMainId:"dragMain",dragTitleId:"dragTitle",closeId:"close",opacity:0.5});
83 </script>
84 </body>
85 </html>