uniapp获取上个月、下个月的月初和月末的日期实现

<template>
  <view>
    <button type="" @click="last()">上一月</button>
    <button type="" @click="next()">下一月</button>
    <view class="" >
      {{startDate}}
    </view>
    <view class="">
      {{endDate}}
    </view>
    
  </view>
</template>

<script>
  export default {
    data() {
      return {
        nowDate:"",
        fullYear:"",
        month:"",
        endOfMonth:"",
        endDate:"",
        startDate:""
      }
    },
    onReady() {
      this.nowDate = new Date();
      this.fullYear =  this.nowDate.getFullYear();
      this.month = this.nowDate.getMonth() + 1; // getMonth 方法返回 0-11，代表1-12月
      this.endOfMonth = new Date(this.fullYear, this.month, 0).getDate(); // 获取本月最后一天
      this.endDate = this.getFullDate(this.nowDate.setDate(this.endOfMonth));//当月最后一天
      this.startDate = this.getFullDate(this.nowDate.setDate(1));//当月第一天
      
    },
    methods: {
      getFullDate(targetDate) {
        var D, y, m, d;
        if (targetDate) {
            D = new Date(targetDate);
            y = D.getFullYear();
            m = D.getMonth() + 1;
            d = D.getDate();
        } else {
            y = fullYear;
            m = month;
            d = date;
        }
        m = m > 9 ? m : '0' + m;
        d = d > 9 ? d : '0' + d;
        return y + '-' + m + '-' + d;
      },
      last(){
        this.nowDate.setMonth(this.nowDate.getMonth()-1);
        this.startDate = this.nowDate.getFullYear() + "-" + (this.nowDate.getMonth()+1) + "-" + this.nowDate.getDate()
        this.endDate =this.getFullDate(new Date(this.nowDate.getFullYear(), this.nowDate.getMonth() + 1, 0)) 
        
      },
      next(){
        this.nowDate.setMonth(this.nowDate.getMonth()+1);
        this.startDate = this.nowDate.getFullYear() + "-" + (this.nowDate.getMonth()+1) + "-" + this.nowDate.getDate()
        this.endDate =this.getFullDate(new Date(this.nowDate.getFullYear(), this.nowDate.getMonth() + 1, 0))
      }
    },
    
  }
</script>

<style>

</style>