vue2.0基于element ui 上月 本月 下月

<div style="margin-bottom:15px ;float:right;">
            <el-button-group>
              <el-button plain @click="time(1)">上一月</el-button>
              <el-button plain @click="time(2)">本月</el-button>
              <el-button plain @click="time(3)">下一月</el-button>
            </el-button-group>
          </div>
time(val) {
      if (val == 1) {
        let myDate = new Date();
        let yy = myDate.getFullYear().toString(); //获取完整的年份(4位)
        let mm = myDate.getMonth() + 1; //获取当前月份(0-11,0代表1月)
        let rr = myDate.getDate(); //获取当前日(1-31)
        let firstDay =
          new Date(yy, mm - 2, 1).getFullYear().toString() +
          "-" +
          (new Date(yy, mm - 2, 1).getMonth() + 1 > 9
            ? new Date(yy, mm - 2, 1).getMonth() + 1
            : "0" + (new Date(yy, mm - 2, 1).getMonth() + 1)) +
          "-" +
          "0" +
          new Date(yy, mm - 2, 1).getDate();
        this.year = new Date(yy, mm - 2, 1).getFullYear().toString();
        this.month =
          new Date(yy, mm - 2, 1).getMonth() + 1 > 9
            ? new Date(yy, mm - 2, 1).getMonth() + 1
            : "0" + (new Date(yy, mm - 2, 1).getMonth() + 1);
        let lastDay =
          new Date(yy, mm - 1, 0).getFullYear().toString() +
          "-" +
          (new Date(yy, mm - 1, 0).getMonth() + 1 > 9
            ? new Date(yy, mm - 1, 0).getMonth() + 1
            : "0" + (new Date(yy, mm - 1, 0).getMonth() + 1)) +
          "-" +
          new Date(yy, mm - 1, 0).getDate();
        // console.log(firstDay);
        // console.log(lastDay);
        this.startTime = firstDay;
        this.endTime = lastDay;
        this.getWeeks();
      } else if (val == 2) {
        this.getdate();
        this.getWeeks();
      } else if (val == 3) {
        let myDate = new Date();
        let yy = myDate.getFullYear().toString(); //获取完整的年份(4位)
        let mm = myDate.getMonth() + 1; //获取当前月份(0-11,0代表1月)
        let rr = myDate.getDate(); //获取当前日(1-31)
        let firstDay =
          new Date(yy, mm, 1).getFullYear().toString() +
          "-" +
          (new Date(yy, mm, 1).getMonth() + 1 > 9
            ? new Date(yy, mm, 1).getMonth() + 1
            : "0" + (new Date(yy, mm, 1).getMonth() + 1)) +
          "-" +
          "0" +
          new Date(yy, mm, 1).getDate();
        this.year = new Date(yy, mm, 1).getFullYear().toString();
        this.month =
          new Date(yy, mm, 1).getMonth() + 1 > 9
            ? new Date(yy, mm, 1).getMonth() + 1
            : "0" + (new Date(yy, mm, 1).getMonth() + 1);
        let lastDay =
          new Date(yy, mm + 1, 0).getFullYear().toString() +
          "-" +
          (new Date(yy, mm + 1, 0).getMonth() + 1 > 9
            ? new Date(yy, mm + 1, 0).getMonth() + 1
            : "0" + (new Date(yy, mm + 1, 0).getMonth() + 1)) +
          "-" +
          new Date(yy, mm + 1, 0).getDate();
        // console.log(firstDay);
        // console.log(lastDay);
        this.startTime = firstDay;
        this.endTime = lastDay;
        this.getWeeks();
      }
    },