js 日期加一个月

function addMonth(date, months) {
  const newDate = new Date(date);
  const expectedMonth = newDate.getMonth() + months;
  newDate.setMonth(expectedMonth);

  // 如果日期超过了新月份的最大天数，就调整到该月的最后一天
  if (newDate.getMonth() !== expectedMonth % 12) {
    newDate.setDate(0);
  }

  return newDate;
}

// 示例用法
const originalDate = new Date('2023-05-31');
const newDate = addMonth(originalDate, 1);
console.log(newDate);