小賴的實戰記錄

var date1 = '2018-05-16';                   
var objDate = new Date(date1 );
objDate .setDate(objDate .getDate() + 1);

var mm = objDate .getMonth() + 1; 
var dd = objDate .getDate();

var date2 = [objDate .getFullYear(),
    (mm>9 ? '' : '0') + mm,
    (dd>9 ? '' : '0') + dd
    ].join('-');