1、根據下標獲取陣列中的一組資料

  let dogs = [
              {
                name:"a"
              },
              {
                name:"b"
              }
            ]


            for (let i = 0; i <dogs.length ; i++) {
              let obj = dogs[i];
              console.log("obj.name:"+obj.name);
              /*
              * obj.name:a
              * obj.name:b
              * */
            }