使用element UI的日期选择器时，默认显示当天日期

  // template
         <el-date-picker
          v-model="searchData.date"
          type="date"
          placeholder="选择日期"
          style="width:150px"
          value-format="yyyy-MM-dd"
          @change="getFilterData"
        />
        
  // js
   data() {
    return {
      searchData: {
        inputValue1: '',
        inputValue2: '',
        date: ''
      }
    }
  },
  mounted() {
    this.getNowTime()
  },
  methods: {
    getFilterData() {
      this.$emit('getFilterData', this.searchData)
    },
    getNowTime() {
      var now = new Date()
      var year = now.getFullYear() // 得到年份
      var month = now.getMonth() // 得到月份
      var date = now.getDate() // 得到日期
      month = month + 1
      month = month.toString().padStart(2, '0')
      date = date.toString().padStart(2, '0')
      var defaultDate = `${year}-${month}-${date}`
      this.$set(this.searchData, 'date', defaultDate)
    }
  }