本文实例讲述了JS实现可拖曳、可关闭的弹窗效果。分享给大家供大家参考。具体如下：
运行该实例，点击文字，弹出一个窗口，其实是一个弹出层，这个弹出层可以随鼠标拖曳，另外，示例演示了用本方法弹出文字层和弹出图片层的具体代码，请根据选择使用哦。
运行效果截图如下：
在线演示地址如下：
http://demo.jb51.net/js/2015/js-draw-close-able-alert-dlg-demo/
具体代码如下：
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>弹出层、弹窗效果+拖曳功能 </title>
<style type="text/css">
*{ margin:0px; padding:0px;}
body{ font-size:12px; font:Arial, Helvetica, sans-serif; margin:25PX 0PX; background:#eee;}
.botton{ color:#F00; cursor:pointer;}
.mybody{width:600px; margin:0 auto; height:1500px; border:1px solid #ccc; padding:20px 25px; background:#fff}
#cwxBg{ position:absolute; display:none; background:#000; width:100%; height:100%; left:0px; top:0px; z-index:1000;}
#cwxWd{ position:absolute; display:none; border:10px solid #CCC; padding:10px;background:#FFF; z-index:1500;}
#cwxCn{ background:#FFF; display:block;}
.imgd{ width:400px; height:300px;}
</style>
</head>
<body>
<!--弹出窗-->
<div class="mybody">
<div class="botton" id="testClick">点击测试</div>
asdasdasdasdasdasdasd<br/>这里是一段文字哦！<div class="botton" id="testClick1">点击测试</div>
</div>
<script type="text/javascript">
C$('testClick').onclick = function(){
var neirong = '<div><img src="http://www.jb51.net/images/logo.gif" class="imgd" / alt="JS实现可拖曳、可关闭的弹窗效果_javascript技巧" ></div>';
cwxbox.box.show(neirong);
}
C$('testClick1').onclick = function(){
var neirong = '123456789132456789';
cwxbox.box.show(neirong,3);
}
function C$(id){return document.getElementById(id);}
//定义窗体对象
var cwxbox = {};
cwxbox.box = function(){
var bg,wd,cn,ow,oh,o = true,time = null;
return {
show:function(c,t,w,h){
if(o){
bg = document.createElement('div'); bg.id = 'cwxBg';
wd = document.createElement('div'); wd.id = 'cwxWd';
cn = document.createElement('div'); cn.id = 'cwxCn';
document.body.appendChild(bg);
document.body.appendChild(wd);
wd.appendChild(cn);
bg.onclick = cwxbox.box.hide;
window.onresize = this.init;
window.onscroll = this.scrolls;
o = false;
}
if(w && h){
var inhtml = '<iframe src="'+ c +'" width="'+ w +'" height="'+ h +'" frameborder="0"></iframe>';
}else{
var inhtml = c;
}
cn.innerHTML = inhtml;
oh = this.getCss(wd,'offsetHeight');
ow = this.getCss(wd,'offsetWidth');
this.init();
this.alpha(bg,50,1);
this.drag(wd);
if(t){
time = setTimeout(function(){cwxbox.box.hide()},t*1000);
}
},
hide:function(){
cwxbox.box.alpha(wd,0,-1);
clearTimeout(time);
},
init:function(){
bg.style.height = cwxbox.page.total(1)+'px';
bg.style.width = '';
bg.style.width = cwxbox.page.total(0)+'px';
var h = (cwxbox.page.height() - oh) /2;
wd.style.top=(h+cwxbox.page.top())+'px';
wd.style.left=(cwxbox.page.width() - ow)/2+'px';
},
scrolls:function(){
var h = (cwxbox.page.height() - oh) /2;
wd.style.top=(h+cwxbox.page.top())+'px';
},
alpha:function(e,a,d){
clearInterval(e.ai);
if(d==1){
e.style.opacity=0;
e.style.filter='alpha(opacity=0)';
e.style.display = 'block';
}
e.ai = setInterval(function(){cwxbox.box.ta(e,a,d)},40);
},
ta:function(e,a,d){
var anum = Math.round(e.style.opacity*100);
if(anum == a){
clearInterval(e.ai);
if(d == -1){
e.style.display = 'none';
if(e == wd){
this.alpha(bg,0,-1);
}
}else{
if(e == bg){
this.alpha(wd,100,1);
}
}
}else{
var n = Math.ceil((anum+((a-anum)*.5)));
n = n == 1 ? 0 : n;
e.style.opacity=n/100;
e.style.filter='alpha(opacity='+n+')';
}
},
getCss:function(e,n){
var e_style = e.currentStyle ? e.currentStyle : window.getComputedStyle(e,null);
if(e_style.display === 'none'){
var clonDom = e.cloneNode(true);
clonDom.style.cssText = 'position:absolute; display:block; top:-3000px;';
document.body.appendChild(clonDom);
var wh = clonDom[n];
clonDom.parentNode.removeChild(clonDom);
return wh;
}
return e[n];
},
drag:function(e){
var startX,startY,mouse;
mouse = {
mouseup:function(){
if(e.releaseCapture)
{
e.onmousemove=null;
e.onmouseup=null;
e.releaseCapture();
}else{
document.removeEventListener("mousemove",mouse.mousemove,true);
document.removeEventListener("mouseup",mouse.mouseup,true);
}
},
mousemove:function(ev){
var oEvent = ev||event;
e.style.left = oEvent.clientX - startX + "px";
e.style.top = oEvent.clientY - startY + "px";
}
}
e.onmousedown = function(ev){
var oEvent = ev||event;
startX = oEvent.clientX - this.offsetLeft;
startY = oEvent.clientY - this.offsetTop;
if(e.setCapture)
{
e.onmousemove= mouse.mousemove;
e.onmouseup= mouse.mouseup;
e.setCapture();
}else{
document.addEventListener("mousemove",mouse.mousemove,true);
document.addEventListener("mouseup",mouse.mouseup,true);
}
}
}
}
}()
cwxbox.page = function(){
return{
top:function(){return document.documentElement.scrollTop||document.body.scrollTop},
width:function(){return self.innerWidth||document.documentElement.clientWidth||document.body.clientWidth},
height:function(){return self.innerHeight||document.documentElement.clientHeight||document.body.clientHeight},
total:function(d){
var b=document.body, e=document.documentElement;
return d?Math.max(Math.max(b.scrollHeight,e.scrollHeight),Math.max(b.clientHeight,e.clientHeight)):
Math.max(Math.max(b.scrollWidth,e.scrollWidth),Math.max(b.clientWidth,e.clientWidth))
}
}
}()
</script>
</body>
</html>
希望本文所述对大家的JavaScript程序设计有所帮助。
