javascript array foreach

 var local_arr2 = {"1":{c10 :'강남구',c11 :'강동구',c12"29"},2:{a10 :'서귀포시',a11 :'제주시',}}; 

var idx2 =$("#local").val();

  console.log("a"+idx2);

          var t=Object.values(local_arr2[idx2]).length;

     $("#local2").append('<option ></option');

   Object.keys(local_arr2[idx2]).forEach(key => {

            $("#local2").append('<option value="' + key + '">'+key+ local_arr2[idx2][key] + '</option');

         });