function $(obj) {
	return document.getElementById(obj);
}

function maskCover(msgw, msgh, title, preopa){
	var opa = preopa ? preopa : 0.9;

	//遮罩背景设置  
	var sWidth,sHeight; 
	sWidth = screen.availWidth; 
	if(screen.availHeight > document.body.scrollHeight){
		sHeight = screen.availHeight;	//少于一屏
	}else{
		sHeight = document.body.scrollHeight;	//多于一屏 
	}
	//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.backgroundColor = '#333333'; 
	maskObj.style.filter = "Alpha(opacity="+opa*100+");"; 
	maskObj.style.opacity = opa; 
	maskObj.style.width = sWidth + "px";
	maskObj.style.height = sHeight + "px";
	maskObj.style.zIndex = "10000"; 
	document.body.appendChild(maskObj);
	//移动屏幕到页顶
	//document.documentElement.scrollTop = 0;
	//隐藏滚动条
	document.body.style.overflowX = 'hidden';//ff
	document.getElementsByTagName('html')[0].style.overflowX = 'hidden';//ie
	//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 +document.documentElement.scrollTop) + "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 = '#FFF';
	msgObj.style.border = "0px solid #8CB5E7"; 
	msgObj.style.zIndex = "10001"; 
	//创建标题
	var thObj = document.createElement("div");
	thObj.setAttribute("id","msgth");
	thObj.className = "DragAble";
	thObj.title = "按住鼠标左键可以拖动窗口";
	thObj.style.cursor = "move";
	thObj.style.padding = "4px 6px 10px 10px";
	thObj.style.color = '#1852A5';
	thObj.style.background = '#EEF5FD';
	thObj.innerHTML = "<img src='/img2/closeCover.jpg' onclick='CloseMsg()' style='float:right;cursor:hand' alt='关闭'><span id='coverTitle' style='font-size:12px;font-weight:bold;'>"+ title +"</span>";
	//创建内容
	var bodyObj = document.createElement("div");
	bodyObj.setAttribute("id","msgbody"); 
	bodyObj.style.padding = "0px";
	bodyObj.style.borderTop = "2px solid #8CB5E7";
	bodyObj.style.lineHeight = "1.5em";
	var txt = document.createTextNode('')
	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");