js判断用户当前地区

<script src="http://pv.sohu.com/cityjson?ie=utf-8"></script>
<script type="text/javascript">
  var city = returnCitySN['cname'];
        guangdong = city.indexOf('广东')
        beijing = city.indexOf('北京')
        shanghai = city.indexOf('上海')
        fujian = city.indexOf('福建')
        console.log(guangdong,fujian,beijing,shanghai)
        if (guangdong >= 0 ||  beijing >= 0 || shanghai >= 0 || fujian >= 0 ) {
            isTrue = true; //不显示
        }else{
            isTrue = false; 
        }
        console.log(isTrue)
        if (isTrue) {
            //不展示广告    
            // alert(city)
            console.log('当前属于不显示区域 '+city);
        }else{

            //展示广告    
            // alert(city)
            console.log('当前属于不显示区域 '+city);
        }
        
</script>