//XML Request 返回同一处理。
//@req newXMLHttpRequest函数实例
//@responseXmlHandler 成功后的回调函数
//@exceptionHandler 请求失败处理的回调函数。如果不指定，则默认用alert处理
function getReadyStateHandler(req, responseXmlHandler, exceptionHandler)
{
	return function ()
	{
		if (req.readyState == 4)// 如果请求的状态是“完成”
		{
			var message = null;
			if (req.status == 200)
			{
				var xml = req.responseXML;
				if (xml == null)
				{
					message = "返回的不是合法的XML串：" + req.responseText;
				}
				else
				{
					var redirect = xml.getElementsByTagName("redirect");
					if (redirect && redirect.length)
					{
						window.location.href = redirect[0].getAttribute("href");
						return;
					}
					var result = xml.getElementsByTagName("result")[0];
					if (result == null || "true" == result.getAttribute("status"))
					{
						responseXmlHandler(result, req);
						return;
					}
					if (result)
					{
						message = result.getAttribute("exception");
					}
				}
			}
			else if (req.status == 12029 || req.status == 0)
			{
				message = "网络不通";
			}
			else if (req.status == 12030)
			{
				message = "后台服务程序内部错误，请刷新重试";
			}
			else if (req.status == 404)
			{
				message = "请求页面不存在" + req.status;
			}
			else if (req.status == 500)
			{
				message = "后台服务程序内部出错";
			}
			else
			{
				message = "非预知错误：" + req.status;
			}
			if(exceptionHandler)
			{
				exceptionHandler(message, req.responseText);
			}
			else
			{
				finishProcess();
				if (message == null) 
				{
					message = req.responseText;
				}
				alert(message);
			}
		}
	}
}

//用于新浏览器的XML HttpRequest
function newXMLHttpRequest()
{
	if (window.XMLHttpRequest) return new XMLHttpRequest();
	else return new ActiveXObject("Msxml2.XMLHTTP");
}

function convertParameter(value)
{
	if (value.indexOf("%") >= 0)
		value = value.replace(/\%/g, "%25");
	if (value.indexOf("&") >= 0)
		value = value.replace(/&/g, "%26");
	if (value.indexOf("=") >= 0)
		value = value.replace(/=/g, "%3d");
	if (value.indexOf(" ") >= 0)
		value = value.replace(/\ /g, "%20");
	if (value.indexOf("?") >= 0)
		value = value.replace(/\?/g, "%3f");	
	return value;
}

/**
 * 提交异步XMLRequest请求。
 * @param postPage 请求页面地址
 * @param postArgumentArray  请求页面传递的参数名机器参数值构成的数组。
 *  如 参数1名称，参数1的值，参数2名称，参数2的值...[参数n名称，参数n的值]
 * @param responseXmlHandler 请求成功后回调的函数名称
 * @param exceptionHandler   如果请求过程出现错误时，错误处理函数名称
 */
function postRequest(postPage, postArgumentArray, responseXmlHandler, exceptionHandler)
{
	try
	{
		if (!prepareProcessWindow("postProgress"))
		{
			return;
		}
		var req = newXMLHttpRequest();
		var exceptionHandle = exception;
		if (exceptionHandler && typeof(exceptionHandler) == "function")
		{
			exceptionHandle = exceptionHandler;
		}
		//alert(exceptionHandle);
		var handlerFunction = getReadyStateHandler(req, responseXmlHandler, exceptionHandle);
		req.onreadystatechange = handlerFunction;
		req.open("POST", postPage, true);
		req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
		var postArgumentList = "";
		for (var i = 0; i < postArgumentArray.length/2; i++)
		{
			var name  = convertParameter(postArgumentArray[i*2]);
			var value = convertParameter(postArgumentArray[i*2 + 1]);
			if (i > 0) postArgumentList += "&";
			postArgumentList += name + "=" + value;
		}
		req.send(postArgumentList);
		postArgumentList = null;
		setTimeout('showProgress("正在处理请求......")', 2000);
	}
	catch(e)
	{
		finishProcess();
		exceptionHandle("程序错误：" + e.name + "，" + e.message);
	}
}

function exception(info, detail)
{
	finishProcess();
	if (info) alert(info);
	else if (detail) alert(detail);
}

//判断参数对象是否为对象数组
function isArray(a)
{
	if(a && a.length
		&& Object.prototype.toString.apply(a).indexOf('[object ') >= 0)
	{
		return true;
	}
	else
	{
		return false;
	}
}

//获得form中某个input对象当前的输入值
function getFieldValue(a)
{
	if (isArray(a))
	{
		for(var i = 0; i < a.length; i++)
		{
			if (a[i].checked)
			{
				return a[i].value;
			}
		}
		return "";
	}
	else if (a && a.value)
	{
		return a.value;
	}
	else
	{
		return "";
	}
}

function focusInput(x)
{
	try
	{
		if (x)
		{
			if(isArray(x) && x[0])
			{
				if (x[0].select) x[0].select();
				x[0].focus();
			}
			else
			{
				if (x.select) x.select();
				x.focus();
			}
		}
	}
	catch(e)
	{
		//alert(e);
	}
}

function getElements(parentNode, subNodeTagName)
{//getElementsByTagName在IE/Chrome流览器中才支持
	return parentNode.getElementsByTagName(subNodeTagName);
}

function getElementAt(parentNode, subNodeTagName, index)
{
	return getElements(parentNode, subNodeTagName)[index];
}

var msg = new Object();

msg.busyMark = false;

msg.createDialog=function(id, isModal)
{
	var dialog = document.createElement("div");
	dialog.className='dialog';
	dialog.id=id;

	var titleBar=document.createElement("div");
	titleBar.className='titleBar';
	var closeButton=document.createElement("span");
	closeButton.dialog=dialog;
	closeButton.onclick=msg.hideDialog;
	closeButton.className='titleButton';
	var closeTxt=document.createTextNode("X");
	closeButton.appendChild(closeTxt);
	titleBar.appendChild(closeButton);
	dialog.appendChild(titleBar);

	var tbl=document.createElement("table");
	dialog.appendChild(tbl);
	dialog.tbod=document.createElement("tbody");
	tbl.appendChild(dialog.tbod);

	if (isModal)
	{
		dialog.modalLayer=document.createElement("div");
		dialog.modalLayer.className='modal';
		dialog.modalLayer.style.display='none';
		dialog.modalLayer.appendChild(dialog);
		document.body.appendChild(dialog.modalLayer);
	}
	else
	{
		dialog.className+= ' non-modal';
		dialog.style.diaplay='none';
		document.body.appendChild(dialog);
	}
	return dialog;
}

msg.hideDialog=function(e)
{
	var dialog=this.dialog?this.dialog:msg.dialog;
	if (dialog)
	{
		if (dialog.modalLayer)
		{
			dialog.modalLayer.style.display='none';
		}
		else
		{
			dialog.style.diaplay='none';
		}
	}
}

msg.showDialog=function(e)
{
	var dialog=this.dialog?this.dialog:msg.dialog;
	if (dialog)
	{
		if (dialog.modalLayer)
		{
			dialog.modalLayer.style.display='block';
		}
		else
		{
			dialog.style.diaplay='block';
		}
	}
}

msg.showMessage=function(message, el)
{
	if (!el) el = msg.dialog.tbod;
	var inTable=(el.tagName=="TBODY");
	var topEl = null;
	var row = document.createElement("tr");
	if (!inTable)
	{
		topEl=document.createElement("table");
		var tbod=document.createElement("tbody");
		topEl.appendChild(tbod);
		tbod.appendChild(row);
	}
	else
	{
		topEl = row;
	}
	var txtTd=document.createElement("td");
	txtTd.valign="top";
	txtTd.className="msg_text";
	row.appendChild(txtTd);
	row = null;
	txtTd.innerHTML=message;
	DM.clearChildNodes(el);
	el.appendChild(topEl);
}

function prepareProcessWindow(id)
{
	msg.dialog = $(id);
	if (!msg.dialog)
	{
		msg.dialog = msg.createDialog(id, true);
	}
	if (msg.busyMark)
	{
		msg.showDialog();
		msg.showMessage("最近一次服务请求尚未执行完毕");
		return false;
	}
	msg.busyMark = true;
	
	return true;
}

function showProgress(message)
{
	if (msg.busyMark)
	{
		msg.showDialog();
		msg.showMessage(message);
	}
}

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

function hideDiv(id)
{
	var t;
	if (id.length) t = $(id);
	else t = id;
	t.style.display="none";
}

function displayBlockDiv(id)
{
	var t;
	if (id.length) t = $(id);
	else t = id;
	t.style.display="block";
}

function finishProcess(id)
{
	if (this.busyMark)
	{
		this.busyMark = false;
	}
	if (msg != null)
	{
		if (msg.busyMark) 
		{
			msg.busyMark = false;
		}
		msg.hideDialog();
	}
}


var DM = new Object();

DM.clearChildNodes = function(dom)
{
	this.tmpDom = null;

	while (dom && dom.lastChild)
	{
		this.tmpDom = dom.removeChild(dom.lastChild);
		if (this.tmpDom.refs)
		{//used in IE
			for (var i in this.tmpDom.refs)
			{
				if (this.tmpDom.refs[i].parentNode)
				{
					var tmpChildDom = this.tmpDom.refs[i].parentNode.removeChild(this.tmpDom.refs[i]);
					delete this.tmpChildDom;
					delete tmpDom.refs[i];
				}
			}
		}
		delete this.tmpDom;
	}
}