设置默认Ajax操作cache and error

    // 设置Ajax操作的默认设置 
    $.ajaxSetup({ 
        cache: false,  
        error: function (XMLHttpRequest, textStatus, errorThrown) { 
            if( typeof(errorThrown) != "undefined" ) 
                $.messager.alert(g_MsgBoxTitle, "调用服务器失败。<br />" + errorThrown ,'error'); 
            else{ 
                var error = "<b style='color: #f00'>" + XMLHttpRequest.status + "  " + XMLHttpRequest.statusText + "</b>"; 
                var start = XMLHttpRequest.responseText.indexOf("<title>"); 
                var end = XMLHttpRequest.responseText.indexOf("</title>"); 
                if( start > 0 && end > start ) 
                    error += "<br /><br />" + XMLHttpRequest.responseText.substring(start + 7, end); 
                    $.messager.alert(g_MsgBoxTitle, "调用服务器失败。<br />" + error ,'error'); 
            } 
        } 
    });