学习使用js给指定日期加减指定天数 具体代码 具体代码 javascript"> function add_day(date, days) {if (days == undefined || days == '') {days = 1;}let date_new = new Date(date);date_new.setDate(date_new.getDate() + days);let month = date_new.getMonth() + 1; //月份从0开始所以需要+1var day = date_new.getDate();if (month < 10) {month = '0' + month;}if (day < 10) {day = '0' + day;}return date_new.getFullYear() + '-' + month + '-' + day;}// 使用示例var currentDate = '2024-04-30';console.log("今天的日期:", currentDate);var newDate = add_day(currentDate, 5);console.log("加上5天后的日期:", newDate);