在使用 vxe-table 时，需要实现表尾合计功能，通过单元格编辑之后，实时自动计算表尾合计的值，自动更新表尾合计数据。

官网：https://vxetable.cn

<template>
  <div>
    <vxe-button status="primary" @click="insertEvent">新增</vxe-button>

    <vxe-table
      border
      show-footer
      show-overflow
      keep-source
      ref="tableRef"
      height="400"
      :footer-data="footerData"
      :data="tableData"
      :edit-config="{trigger: 'click', mode: 'row', showStatus: true}">
      <vxe-column field="seq" type="seq" width="60"></vxe-column>
      <vxe-colgroup title="统计信息">
        <vxe-column field="name" title="Name" :edit-render="{name: 'VxeInput'}">
          <template #edit="{ row }">
            <vxe-input v-model="row.name"></vxe-input>
          </template>
        </vxe-column>
        <vxe-column field="age" title="Age" :edit-render="{name: 'VxeNumberInput'}">
          <template #edit="{ row }">
            <vxe-number-input v-model="row.age" type="integer" :min="1" :max="120" @change="updateFootEvent"></vxe-number-input>
          </template>
        </vxe-column>
        <vxe-column field="num" title="Num" :edit-render="{name: 'VxeNumberInput'}">
          <template #edit="{ row }">
            <vxe-number-input v-model="row.num" @change="updateFootEvent"></vxe-number-input>
          </template>
        </vxe-column>
        <vxe-column field="rate" title="Rate" :edit-render="{name: 'VxeNumberInput'}">
          <template #edit="{ row }">
            <vxe-number-input v-model="row.rate" @change="updateFootEvent"></vxe-number-input>
          </template>
        </vxe-column>
      </vxe-colgroup>
      <vxe-column field="action" title="操作" width="100">
        <template #default="{row }">
          <vxe-button mode="text" status="error" @click="removeRow(row)">删除</vxe-button>
        </template>
      </vxe-column>
    </vxe-table>
  </div>
</template>

<script setup>
import { ref } from 'vue'
import { VxeUI } from 'vxe-table'

const tableRef = ref()

const tableData = ref([
  { id: 10001, name: 'Test1', role: 'Develop', age: 10, num: 28, rate: 5, address: 'test abc' },
  { id: 10002, name: 'Test2', role: 'Test', age: 34, num: 22, rate: 4, address: 'Guangzhou' },
  { id: 10003, name: 'Test3', role: 'PM', age: 56, num: 32, rate: 3, address: 'Shanghai' },
  { id: 10004, name: 'Test4', role: 'Designer', age: 45, num: 24, rate: 1, address: 'Shanghai' },
  { id: 10005, name: 'Test5', role: 'PM', age: 56, num: 32, rate: 4, address: 'Shanghai' },
  { id: 10006, name: 'Test6', role: 'Designer', age: 45, num: 24, rate: 1, address: 'Shanghai' }
])

const footerData = ref([
  { seq: '平均', name: '-', age: 0, rate: 0, num: 0 },
  { seq: '和值', name: '-', age: 0, rate: 0, num: 0 }
])

const meanNum = (list, field) => {
  let count = 0
  list.forEach(item => {
    count += Number(item[field])
  })
  return (count / list.length).toFixed(2)
}

const sumNum = (list, field) => {
  let count = 0
  list.forEach(item => {
    count += Number(item[field])
  })
  return count.toFixed(2)
}

const insertEvent = async () => {
  const record = {
    name: 'New name'
  }
  const $table = tableRef.value
  if ($table) {
    const { row: newRow } = await $table.insert(record)
    $table.setEditCell(newRow, 'age')
  }
}

const removeRow = async (row) => {
  const $table = tableRef.value
  if ($table) {
    const type = await VxeUI.modal.confirm('您确定要删除该数据?')
    if (type === 'confirm') {
      await $table.remove(row)
      updateFootEvent()
    }
  }
}

// 在值发生改变时更新表尾合计
const updateFootEvent = () => {
  const $table = tableRef.value
  if ($table) {
    const { visibleData } = $table.getTableData()
    updateFootCount(visibleData)
  }
}

const updateFootCount = (list) => {
  const [meanObj, sumNObj] = footerData.value
  meanObj.age = meanNum(list, 'age')
  meanObj.num = meanNum(list, 'num')
  meanObj.rate = meanNum(list, 'rate')
  sumNObj.age = sumNum(list, 'age')
  sumNObj.num = sumNum(list, 'num')
  sumNObj.rate = sumNum(list, 'rate')
}

updateFootCount(tableData.value)
</script>

https://gitee.com/xuliangzhan/vxe-table