::: vue-playground VUE-文档计算

@file spreadSheetStore.ts

import { type Reactive, reactive } from 'vue'

const COLS = 3
const ROWS = 3

export const cells: Reactive<string[][]> = reactive(
  Array.from(Array(COLS).keys()).map(() =>
    Array.from(Array(ROWS).keys()).map(() => '')
  )
)

// initial state for demo
cells[0][0] = '1'
cells[0][1] = '2'
cells[0][2] = '= A0 + A1'

// adapted from https://codesandbox.io/s/jotai-7guis-task7-cells-mzoit?file=/src/atoms.ts
// by @dai-shi
export function evalCell(exp: string) {
  if (!exp.startsWith('=')) {
    return exp
  }

  // = A1 + B2 ---> get(0,1) + get(1,2)
  exp = exp
    .slice(1)
    .replace(
      /\b([A-Z])(\d{1,2})\b/g,
      (_: any, c: string, r: any) => `get(${c.charCodeAt(0) - 65},${r})`
    )

  try {
    return new Function('get', `return ${exp}`)(getCellValue)
  } catch (e) {
    return `#ERROR ${e}`
  }
}

function getCellValue(c: number, r: number) {
  const val = evalCell(cells[c][r])
  const num = Number(val)
  return Number.isFinite(num) ? num : val
}

@file SpreadSheetCell.vue

<script setup lang="ts">
import { ref } from "vue";
import { cells, evalCell } from "./spreadSheetStore.ts";

interface CellProps {
  c: number;
  r: number;
}

type ElType = {
  el: HTMLInputElement;
};

const props = withDefaults(defineProps<CellProps>(), {
  c: 0,
  r: 0,
});

const editing = ref(false);

function update(e: Event) {
  editing.value = false;
  if (typeof props.c !== "undefined" && typeof props.r !== "undefined") {
    const target = e.target as HTMLInputElement;
    cells[props.c][props.r] = target.value.trim();
  }
}
</script>

<template>
  <div class="cell" :title="cells[c][r]" @click="editing = true">
    <input
      v-if="editing"
      :value="cells[c][r]"
      @change="update"
      @blur="update"
      @vue:mounted="({ el }: ElType) => el.focus()"
    />
    <span v-else>{{ evalCell(cells[c][r]) }}</span>
  </div>
</template>

<style scoped>
.cell,
.cell input {
  height: 1.5em;
  line-height: 1.5;
  font-size: 15px;
  color: #000000;
}

.cell span {
  padding: 0 6px;
}

.cell input {
  width: 100%;
  box-sizing: border-box;
  padding: 0 4px;
}

.cell input:focus {
  border: 1px solid #f1f1f1;
  color: #000000;
}
</style>

@file App.vue

<script setup lang="ts">
import Cell from "./SpreadSheetCell.vue";
import { cells } from "./spreadSheetStore.ts";

const cols = cells.map((_, i) => String.fromCharCode(65 + i));
</script>

<template>
  <table>
    <thead>
      <tr>
        <th></th>
        <th v-for="c in cols">{{ c }}</th>
      </tr>
    </thead>
    <tbody>
      <tr v-for="i in cells[0].length">
        <th>{{ i - 1 }}</th>
        <td v-for="j in cols.length">
          <Cell :r="i - 1" :c="j - 1"></Cell>
        </td>
      </tr>
    </tbody>
  </table>
</template>

<style scoped>
th {
  color: #000000;
  background-color: #f1f1f1;
  padding: 0 1em;
}

tr:first-of-type th {
  width: 100px;
}

tr:first-of-type th:first-of-type {
  width: 25px;
}

td {
  border: 1px solid #3c3c3c4a;
  padding: 0;
}
</style>

@setting

{
  "showCompileOutput": false
}

:::

表格行列间的计算

new Function('get', `return ${exp}`)(getCellValue)

具体步骤如下：

• 使用 new Function 创建一个匿名函数，该函数接受一个参数 get。
• 匿名函数的函数体为 return ${exp}，其中 exp 是一个字符串表达式。
• 执行这个匿名函数，并将 getCellValue 传递给它作为参数。