Ajax在Safari和Chrome中不起作用

Question

I am trying the following code. its working fine in firefox, but its not working in chrome or safari.

if (getCookie("vantage_device_id")==''){
    $.ajax({url:"get_last_device.php"}).done(function(last_visitor_id){
        deviceID = ++last_visitor_id;
        //alert ("device ID " + deviceID);
        console.log("creating cookies");
        setCookie("vantage_device_id", deviceID , 365);

        $.ajax({
            url:"save_device.php?deviceID="+deviceID+"&websiteID="+WebsiteID+"&width="+sWidth+"&height="+sHeight,
            success:function(datasource){
                //alert (datasource);
            }
        });    

        $.ajax({
            url:"save_session.php?deviceID="+deviceID+"&websiteID="+WebsiteID+"&url="+url,
            success:function(filename){
                // saving session data for individual pages ///////////////
                //alert ("File Name " + filename);
            }
        });
    });
} else {
    deviceID = getCookie("vantage_device_id");
    //alert ("Cookies already exists...." + deviceID);
    $.ajax({
        url:"save_session.php?deviceID="+deviceID+"&websiteID="+WebsiteID+"&url="+url,
        success:function(filename){
            // saving session data for individual pages ///////////////
            //alert ("File Name " + filename);
        }
    }); 
}

I am getting the following error:

Uncaught ReferenceError: $ is not defined script.js:28 (anonymous function)

and this is line 28 :

$.ajax({url:"get_last_device.php"}).done(function(last_visitor_id){

I have copied the jquery from google ( http://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js )

can anyone suggest any solution. any help is apriciated.

Regards,

Answer 1

确保在尝试使用jQuery之前（在页面顶部附近）导入jQuery。

<script src="//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>