A DIV written in JavaScript pops up a web page dialog box_javascript skills

function MessageBox( )
{
this.titleheight = "21"; // Prompt window title height
this.bordercolor = "#666699"; // Prompt window border color
this.titlecolor = "# 1259a4"; // Title color of the prompt window
this.titlebgcolor = "#e4f1fb"; // Title background color of the prompt window
this.bgcolor = "#FFFFFF"; // Background color of the prompt content
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 = " ×Close window";
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 = "";
}
msgBox.innerHTML = "

" msg "

";

if(document.getElementById("frmAlertWin") != null)
{
document.getElementById("frmAlertWin").src = framesrc;
}


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