function getAjaxData(urlstr, callback_func, options){  
    var myurl = AJAX_HEADER + urlstr + AJAX_TAIL;  
    var isAsync = true;//初始化是否同步的属性设置  
    var nTimeout = AJAX_TIMEOUT;//初始化请求超时的数据  
    var errorCallback = null;  
    //利用JSON对象options来修改默认初始化的属性,这样一个参数可以设置多个属性  
    if (options)  
    {  
        if (options.sync) //sync这个参数就是JSON的对象  
        {  
            isAsync = (options.sync === true) ? false : true;  
        }  
        if (options.timeout)  
        {  
            nTimeout = parseInt(options.timeout);  
            if (isNaN(nTimeout))  
                nTimeout = AJAX_TIMEOUT;  
        }  
        errorCallback = options.errorCB;  
    }  
      
    if ($.browser.mozilla)   
    {  
        try   
        {  
            //netscape.security.PrivilegeManager.enablePrivilege("UniversalBrowserRead");  
        }   
        catch (exception)   
        {  
            log.error(exception);  
        }  
    }  
    $.ajax({  
        async: isAsync,  
        //cache: false,  
        type: "GET",  
        timeout: nTimeout,  
        url: myurl,  
        //dataType: ($.browser.msie) ? "text" : "xml",  
        error: function(XMLHttpRequest, textStatus){  
            try  
            {  
                if (
jquery.isFunction(errorCallback))  
                {  
                    errorCallback(XMLHttpRequest, textStatus);  
                }  
                log.error("MAIN : getAjaxData(" + myurl + ") error.");  
                log.error("MAIN : XMLHttpRequest.readyState = " + XMLHttpRequest.readyState);  
                log.error("MAIN : XMLHttpRequest.status = " + XMLHttpRequest.status);  
                log.error("MAIN : textStatus " + textStatus);  
            }  
            catch (exception)   
            {  
                log.error(exception);  
            }  
        },  
        success: function(data){  
            log.debug("MAIN : getAjaxData(" + myurl + ") sucess.");  
            log.trace(data);  
            var xml;  
            if (typeof data == "string" || typeof data == "number")   
            {  
                if (!window.ActiveXObject)   
                {  
                    var parser = new DOMParser();  
                    xml = parser.parseFromString(data, "text/xml");  
                }  
                else   
                {  
                    //IE  
                    xml = new ActiveXObject("Microsoft.XMLDOM");  
                    xml.async = false;  
                    xml.loadXML(data);  
                }  
            }  
            else   
            {  
                xml = data;  
            }  
            if (typeof callback_func == "function")   
            {  
                callback_func($(xml));  
            }  
            else   
            {  
                log.error("callback_func is undefined or not a function");  
            }  
        }  
    });  
}  
  
  getAjaxData("api/monitoring/status", function($xml){  
        var wlan_ret = xml2object($xml);  
        if(wlan_ret.type == "response")  
        {  
            monitoring_status = wlan_ret.response;      
            setCurrrentUserHTML();  
        }      
    },  
    {  
        sync:true   //通过JSON传递多个数据,防止数据冗余,这里类似于配置信息  
    });