vue3 中实现 Element Plus 表格合并的方法

<template>
  <el-table :data="tableData" :span-method="arraySpanMethod" border>
    <el-table-column prop="id" label="ID" width="180"></el-table-column>
    <el-table-column prop="name" label="Name" width="180"></el-table-column>
    <el-table-column prop="amount" label="Amount"></el-table-column>
  </el-table>
</template>
<script setup>
const tableData = [
  { id: '1', name: 'Apple', amount: '10' },
  { id: '1', name: 'Apple', amount: '20' },
  { id: '2', name: 'Orange', amount: '30' },
  { id: '2', name: 'Orange', amount: '40' },
  { id: '3', name: 'Banana', amount: '50' },
]
const arraySpanMethod = ({ row, column, rowIndex, columnIndex }) => {
  if (columnIndex === 0) {
    if (rowIndex % 2 === 0) {
      return [2, 1]
    } else {
      return [0, 0]
    }
  }
}
</script>

const getSpanArr = (data) => {
  const spanArr = []
  let pos = 0
  for (let i = 0; i < data.length; i++) {
    if (i === 0) {
      spanArr.push(1)
      pos = 0
    } else {
      if (data[i].id === data[i - 1].id) {
        spanArr[pos] += 1
        spanArr.push(0)
      } else {
        spanArr.push(1)
        pos = i
      }
    }
  }
  return spanArr
}
const spanArr = getSpanArr(tableData)
const objectSpanMethod = ({ row, column, rowIndex, columnIndex }) => {
  if (columnIndex === 0 || columnIndex === 1) {
    const _row = spanArr[rowIndex]
    const _col = _row > 0 ? 1 : 0
    return [_row, _col]
  }
}

const multiSpanMethod = ({ row, column, rowIndex, columnIndex }) => {
  if (columnIndex === 0) {
    if (rowIndex % 3 === 0) {
      return [3, 1]
    } else {
      return [0, 0]
    }
  } else if (columnIndex === 1) {
    if (rowIndex % 2 === 0) {
      return [2, 1]
    } else {
      return [0, 0]
    }
  }
}