老师，这样完善可以吗？includes（）方法第二个参数传-1是判断最后一位吗？

<script>

        //应用

        let url = 'https://www.imooc.com/course/list';

        // const addURLParam = (url,name,value)=>{

        //     //先判断有没有‘？’如果没有就加上？,有的话加上&

        //     url += url.includes('?')?'&':'?';

        //     //再添加名值对

        //      url += `${name}=${value}`;

        //     return url;

        // };

        //完善版本

        const addURLParam = (url,name,value)=>{

            if(url.includes('?',-1)){

                url += `&${name}=${value}`;

            }else{

                url +=`?${name}=${value}`;

            }

            return url;

        };

        url = addURLParam(url,'c','fe');

        console.log(url);

        url = addURLParam(url,'sort','pop');

        console.log(url);

  </script>

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