获取昨天，上个月，过去7天，过去14天，过去N天都可以等

过去N天,爽得一批

//过去7天，过去14天，过去30天   想要过去几天参数就传几就行了 
getBeforeDate(n) {
      var n = n;
      var d = new Date();
      var year = d.getFullYear();
      var mon = d.getMonth() + 1;
      var day = d.getDate();
      if (day <= n) {
        if (mon > 1) {
          mon = mon - 1;
        } else {
          year = year - 1;
          mon = 12;
        }
      }
      d.setDate(d.getDate() - n);
      year = d.getFullYear();
      mon = d.getMonth() + 1;
      day = d.getDate();
      let s =
        year +
        "-" +
        (mon < 10 ? "0" + mon : mon) +
        "-" +
        (day < 10 ? "0" + day : day);
      return s;
    },


//

console.log(this.getBeforeDate(1),'88888')  // 2023-03-02

console.log(this.getBeforeDate(5),'88888') //  2023-02-26

 默认半年前

 

// 获取近半年时间
const getNowdate=(time = 6)=> {
  let date = new Date()
  let year = date.getFullYear()
  let month = date.getMonth()
  let olddate = new Date(year, month - time).getTime()
  let date2 = new Date(olddate);
  let year2 = date2.getFullYear();
  let month2 = date2.getMonth() + 1;
  month2 = (month2<10)? '0'+ month2 : month2;
  
  let currentDate = year2 + "-" + month2
  console.log(currentDate,'半年前的月份')
}
const formatDateMy=() =>{
    let date = new Date();
    let year = date.getFullYear();
    let month = date.getMonth() + 1;
    month = (month<10)? '0'+ month : month;
    let currentDate = year + "-" + month 
    console.log(currentDate,'现在的月份')
    return currentDate;
}