element Ui 分页size-change事件触发同时也出发了current-change事件，导致调用两次接口

<el-pagination 
  @size-change="handleSizeChange"
  @current-change="handleCurrentChange" 
  :current-page.sync="pageInfo.PageNum" 
  :page-sizes="[5, 10, 20]"
  :page-size="pageInfo.PageSize" 
   layout="total, sizes, prev, pager, next, jumper" :total="pageInfo.Total">
</el-pagination> 

    //pageSize变化事件
   handleSizeChange(val) {
        this.$emit("sizeChange", val);
  },

  //pageNum变化事件
  handleCurrentChange() {
    this.$emit("pageNumCheng");
  }