JavaScript写的一个DIV 弹出网页对话框

网上搜索到的代码,做了一些修改该,
修正无法自定义颜色,修正IE8 下错误,以及其他小BUG 兼容IE6~8以及火狐
可以自定义
// 提示窗口标题高度
// 提示窗口的边框颜色
// 提示窗口的标题颜色
// 提示窗口的标题背景色
// 提示内容的背景色
// 提示内容文字对齐方式
功能 可以弹出一个大DIV遮住页面(IE下 透明) 然后在屏幕中央显示显示一个小DIV
可用作功能提示 操作提示 以及公告等
提示内容可以使带HTML标记的文字,也可是一个页面链接

function MessageBox() 
{ 
this.titleheight = "21"; // 提示窗口标题高度 
this.bordercolor = "#666699"; // 提示窗口的边框颜色 
this.titlecolor = "#1259a4"; // 提示窗口的标题颜色 
this.titlebgcolor = "#e4f1fb"; // 提示窗口的标题背景色 
this.bgcolor = "#FFFFFF"; // 提示内容的背景色 
this.MsgAlign="left"; this.Show=function(title, msg, framesrc, w, h) 
{ 
var iWidth = document.documentElement.clientWidth; 
var iHeight = document.documentElement.clientHeight+document.documentElement.scrollTop*2; 
var bgObj = document.createElement("div"); 
bgObj.style.cssText = "position:absolute;left:0px;top:0px;width:"+iWidth+"px;height:"+Math.max(document.body.clientHeight, iHeight)+"px;filter:Alpha(Opacity=30);opacity:0.3;background-color:#000000;z-index:101;"; 
document.body.appendChild(bgObj); 
var msgObj=document.createElement("div"); 
msgObj.style.cssText = "position:absolute;font:11px '宋体';top:"+(iHeight-h)/2+"px;left:"+(iWidth-w)/2+"px;width:"+w+"px;height:"+h+"px;text-align:center;border:1px solid "+this.bordercolor+";background-color:"+this.bgcolor+";padding:1px;line-height:22px;z-index:102;"; 
document.body.appendChild(msgObj); 
var table = document.createElement("table"); 
msgObj.appendChild(table); 
table.style.cssText = "margin:0px;border:0px;padding:0px;"; 
table.cellSpacing = 0; 
var tr = table.insertRow(-1); 
var titleBar = tr.insertCell(-1); 
titleBar.style.cssText = ";width:"+(w-84)+"px;height:"+this.titleheight+"px;text-align:left;padding:3px;margin:0px;font:bold 13px '宋体';color:"+this.titlecolor+";cursor:move;background-color:" + this.titlebgcolor; 
titleBar.style.paddingLeft = "10px"; 
titleBar.innerHTML = title; 
var moveX = 0; 
var moveY = 0; 
var moveTop = 0; 
var moveLeft = 0; 
var moveable = false; 
var docMouseMoveEvent = document.onmousemove; 
var docMouseUpEvent = document.onmouseup; 
titleBar.onmousedown = function(){ 
var evt = getEvent(); 
moveable = true; 
moveX = evt.clientX; 
moveY = evt.clientY; 
moveTop = parseInt(msgObj.style.top); 
moveLeft = parseInt(msgObj.style.left); 
document.onmousemove = function(){ 
if (moveable) 
{ 
var evt = getEvent(); 
var x = moveLeft + evt.clientX - moveX; 
var y = moveTop + evt.clientY - moveY; 
if ( x > 0 &&( x + w < iWidth) && y > 0 && (y + h < iHeight) ) 
{ 
msgObj.style.left = x + "px"; 
msgObj.style.top = y + "px"; 
} 
} 
}; 
document.onmouseup = function (){ 
if (moveable) 
{ 
document.onmousemove = docMouseMoveEvent; 
document.onmouseup = docMouseUpEvent; 
moveable = false; 
moveX = 0; 
moveY = 0; 
moveTop = 0; 
moveLeft = 0; 
} 
}; 
} 
var closeBtn = tr.insertCell(-1); 
closeBtn.style.cssText = "cursor:pointer; padding:2px;background-color:" + this.titlebgcolor; 
closeBtn.innerHTML = "<span style="font-size:10pt;color:"+this.titlecolor+";" style="font-size:10pt;color:"+this.titlecolor+";" id='closeBtn'>×关闭窗口"; 
closeBtn.onclick = function(){ 
document.body.removeChild(bgObj); 
document.body.removeChild(msgObj); 
} 
var msgBox = table.insertRow(-1).insertCell(-1); 
msgBox.style.cssText = "font:10pt '宋体';"; 
msgBox.colSpan = 2; 
if(framesrc != "") 
{ 
msg = "<iframe name='frmAlertWin' id='frmAlertWin' src="about:blank" src="about:blank" frameborder=0 marginwidth=0 marginheight=0 style='height:"+(h-this.titleheight-10)+"px;width:100%;'></iframe>"; 
} 
msgBox.innerHTML = "<div style="\" style="\""text-align:"+this.MsgAlign+";\">"+msg+"</div>"; 
if(document.getElementById("frmAlertWin") != null) 
{ 
document.getElementById("frmAlertWin").src = framesrc; 
} 

function getEvent(){ 
return window.event || arguments.callee.caller.arguments[0]; 
} 
} 
}

调用方式
var msgbox=new MessageBox();
msgbox.Show('站内公告',"小小提示","",500,220);///参数:标题,内容(提示为连接页面时可为空),连接页面地址(使用文字是可为空),宽度,高度
要注意的是如果在页面加载时就要弹出提示 请将调用代码放在body标记以后 否则在IE8下回出现错误