通过js,校验日期格式是否为yy-mm-dd

function checkDate(date){         if(date == "") {                 return true;         }                 var r = date.match(/^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2})$/);                     if (r==null) {                 return false;             }         else {                 return true;             } }