这是个功能很好，且容易调用和控制的弹出层。感兴趣的朋友可以调试运行一下看看效果如何~O(∩_∩)O~

弹出窗口(可拖动，背景灰色透明)*{padding:0; margin:0}.close{float:right;cursor:default}")
function $(id){ return document.getElementById(id)}
function AlertMsg(title,content){
var msgw,msgh,msgbg,msgcolor,bordercolor,titlecolor,titlebg,con;
con = "分类：确定　取消";
//弹出窗口设置
msgw = 300; //窗口宽度
msgh = 150; //窗口高度
msgbg = "#FFF"; //内容背景
msgcolor = "#000"; //内容颜色
bordercolor = "#000"; //边框颜色
titlecolor = "#FFF"; //标题颜色
titlebg = "#369"; //标题背景
//遮罩背景设置
var sWidth,sHeight;
sWidth = screen.availWidth;
sHeight = document.body.scrollHeight;
//创建遮罩背景
var maskObj = document.createElement("div");
maskObj.setAttribute('id','maskdiv');
maskObj.style.position = "absolute";
maskObj.style.top = "0";
maskObj.style.left = "0";
maskObj.style.background = "#777";
maskObj.style.filter = "Alpha(opacity=30);";
maskObj.style.opacity = "0.3";
maskObj.style.width = sWidth + "px";
maskObj.style.height = sHeight + "px";
maskObj.style.zIndex = "10000";
document.body.appendChild(maskObj);
//创建弹出窗口
var msgObj = document.createElement("div")
msgObj.setAttribute("id","msgdiv");
msgObj.style.position ="absolute";
msgObj.style.top = (screen.availHeight - msgh) / 4 + "px";
msgObj.style.left = (screen.availWidth - msgw) / 2 + "px";
msgObj.style.width = msgw + "px";
msgObj.style.height = msgh + "px";
msgObj.style.fontSize = "12px";
msgObj.style.background = msgbg;
msgObj.style.border = "1px solid " + bordercolor;
msgObj.style.zIndex = "10001";
//创建标题
var thObj = document.createElement("div");
thObj.setAttribute("id","msgth");
thObj.className = "DragAble";
thObj.style.cursor = "move";
thObj.style.padding = "4px 6px";
thObj.style.color = titlecolor;
thObj.style.background = titlebg;
var titleStr = "关闭"+""+ title +"";
thObj.innerHTML = titleStr;
//创建内容
var bodyObj = document.createElement("div");
bodyObj.setAttribute("id","msgbody");
bodyObj.style.padding = "10px";
bodyObj.style.lineHeight = "1.5em";
bodyObj.innerHTML = con;
var txt = document.createTextNode(content)
bodyObj.appendChild(txt);
//生成窗口
document.body.appendChild(msgObj);
$("msgdiv").appendChild(thObj);
$("msgdiv").appendChild(bodyObj);
}
function CloseMsg(){
//移除对象
document.body.removeChild($("maskdiv"));
$("msgdiv").removeChild($("msgth"));
$("msgdiv").removeChild($("msgbody"));
document.body.removeChild($("msgdiv"));
}
//拖动窗口
var ie = document.all; 
var nn6 = document.getElementById&&!document.all; 
var isdrag = false; 
var y,x; 
var oDragObj; 
function moveMouse(e) { 
if (isdrag) { 
oDragObj.style.top = (nn6 ? nTY + e.clientY - y : nTY + event.clientY - y)+"px"; 
oDragObj.style.left = (nn6 ? nTX + e.clientX - x : nTX + event.clientX - x)+"px"; 
return false; 
} 
} 
function initDrag(e) { 
var oDragHandle = nn6 ? e.target : event.srcElement; 
var topElement = "HTML"; 
while (oDragHandle.tagName != topElement && oDragHandle.className != "DragAble") { 
oDragHandle = nn6 ? oDragHandle.parentNode : oDragHandle.parentElement; 
} 
if (oDragHandle.className=="DragAble") { 
isdrag = true; 
oDragObj = oDragHandle.parentNode; 
nTY = parseInt(oDragObj.style.top); 
y = nn6 ? e.clientY : event.clientY; 
nTX = parseInt(oDragObj.style.left); 
x = nn6 ? e.clientX : event.clientX; 
document.onmousemove = moveMouse; 
return false; 
} 
} 
document.onmousedown = initDrag; 
document.onmouseup = new Function("isdrag=false"); 
//-->
" _ue_custom_node_="true">

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