/*
* @params date 日期
* @params type 类型 prev/current/next 昨天/今天/明天
* @params fmt 日期拼接符
*/
function getDays(date, type, fmt) {
let currentDate = new Date(date)
let y = currentDate.getFullYear()
let m = currentDate.getMonth() + 1
let d = currentDate.getDate()
function dateFormat(date, fmt) {
let y = new Date(date).getFullYear()
let m = new Date(date).getMonth() + 1
let d = new Date(date).getDate()
return `${y}${fmt}${m}${fmt}${d}`
}
switch (type) {
case "prev":
if (d - 1 < 1) {
if (m - 1 < 1) {
y = y - 1
m = 12
} else {
m = m - 1
}
d = new Date(y, m, 0).getDate()
} else {
d = d - 1
}
break
case "current":
break
case "next":
if (d + 1 > new Date(y, m, 0).getDate()) {
if (m + 1 > 12) {
y = y + 1
m = 1
d = 1
} else {
m = m + 1
d = 1
}
} else {
d = d + 1
}
break;
default:
break;
}
return dateFormat(new Date(`${y}-${m}-${d}`), fmt)
}
console.log(getDays(new Date('2021-1-1'), "prev", "-"));
本文转自：辰漪个人博客
