abbott-methods/src/date/dateMonthPrev.ts

abbott,methods,method,functions,function

import {timeNewDate} from '../time/timeNewDate'
import {timeGetYear} from '../time/timeGetYear'
import {timeGetMonth} from '../time/timeGetMonth'
import {dateApart} from './dateApart'
import {dateMonthHead} from './dateMonthHead'

/**
 * @description 获取日期上月的年月
 * @param {*} [dateValue]
 * @param {Boolean} [isResultArray] 是否返回数组形式，若false则返回字符串，默认为false
 * @returns {Array|String|Null}
 */
export const dateMonthPrev = (
  dateValue: any = new Date(),
  isResultArray: boolean
): string | string[] | null => {
  const theObject = timeNewDate(dateValue)
  if (theObject) {
    const apart = dateApart(dateMonthHead(dateValue), -1)
    const year = timeGetYear(apart) as string
    const month = timeGetMonth(apart) as string
    isResultArray = isResultArray || false
    return isResultArray ? [year, month] : `${year}-${month}`
  } else {
    return null
  }
}