//ajax函數(shù)
var http_request = false;
function send_request(url)
{
	//初始化、指定處理函數(shù)、發(fā)送請求的函數(shù)
	http_request = false;
	//開始初始化XMLHttpRequest對象
	if(window.XMLHttpRequest)
	{
		http_request = new XMLHttpRequest(); //Mozilla 瀏覽器
		if (http_request.overrideMimeType)
		{
			http_request.overrideMimeType('text/xml'); //設置MiME類別
		}
	}
	else if (window.ActiveXObject)
	{
		try{http_request = new ActiveXObject("Msxml2.XMLHTTP");} //IE瀏覽器
		catch (e)
		{
			try {http_request = new ActiveXObject("Microsoft.XMLHTTP");}
			catch (e) {}
		}
	}
	if (!http_request)
	{
		window.alert("不能創(chuàng)建XMLHttpRequest對象實例."); //異常，創(chuàng)建對象實例失敗
		return false;
	}
	http_request.open("GET",url,true); // 確定發(fā)送請求的方式和URL以及是否同步執(zhí)行下段代碼
	http_request.send(null);
}