// 判斷瀏覽器類型
// 參考 http://www.mozilla.org/docs/web-developer/sniffer/browser_type.html

var clientPC = navigator.userAgent.toLowerCase(); // Get client info
var clientVer = parseInt(navigator.appVersion); // Get browser version

var is_ie = ((clientPC.indexOf("msie") != -1) && (clientPC.indexOf("opera") == -1));
var is_nav = ((clientPC.indexOf('mozilla')!=-1) && (clientPC.indexOf('spoofer')==-1)
   	            && (clientPC.indexOf('compatible') == -1) && (clientPC.indexOf('opera')==-1)
       	        && (clientPC.indexOf('webtv')==-1) && (clientPC.indexOf('hotjava')==-1));
var is_moz = 0;

var is_win = ((clientPC.indexOf("win")!=-1) || (clientPC.indexOf("16bit") != -1));
var is_mac = (clientPC.indexOf("mac")!=-1);

// 全域變數 ------------------------------------------------------------------------
var xmlhttp = getXMLHttpRequestObject();	// XMLHttpRequest 物件

// 建立 XMLHttpRequest 物件 ----------------------------------------------------------
// 參考 http://www.peej.co.uk/articles/rich-user-experience.html
function getXMLHttpRequestObject()
{
	var req = false;
    if(window.XMLHttpRequest) {
    	try {
			req = new XMLHttpRequest();
        } catch(e) {
			req = false;
        }
    } else if(window.ActiveXObject) {
       	try {
        	req = new ActiveXObject("Msxml2.XMLHTTP");
      	} catch(e) {
        	try {
          		req = new ActiveXObject("Microsoft.XMLHTTP");
        	} catch(e) {
          		req = false;
        	}
		}
    }
	return req;
}