vue selección completa y pequeña selección

vue3

<template>
  <div>
    <el-checkbox label="全选" v-model="allChecked"></el-checkbox>
    <el-checkbox
      v-for="(item, index) in arr"
      :key="index"
      v-model="item.checked"
      :label="item.name"
      size="large"
    />
  </div>
</template>

<script>
import { computed, ref } from "vue";
export default {
  setup() {
    const arr = ref([
      {
        name: "选项一",
        checked: true,
      },
      {
        name: "选项二",
        checked: true,
      },
      {
        name: "选项三",
        checked: true,
      },
      {
        name: "选项四",
        checked: false,
      },
    ]);

    const allChecked = computed({
      get() {
        return arr.value.every((item) => item.checked);
      },
      set(newVal) {
        arr.value.forEach((item) => (item.checked = newVal));
      },
    });
    return { arr, allChecked };
  },
};
</script>

vue2

<template>
  <div id="app">
     <el-checkbox
      label="全选"
      v-model="allChecked"
    ></el-checkbox>
    <el-checkbox
      v-for="(item, index) in arr"
      :key="index"
      v-model="item.checked"
      :label="item.name"
      size="large"
    />
  </div>
</template>

<script>

export default {
  name: 'App',
  data () {
    return {
      arr: [
        {
          name: '选项一',
          checked: true
        },
        {
          name: '选项二',
          checked: true
        },
        {
          name: '选项三',
          checked: true
        },
        {
          name: '选项四',
          checked: false
        }
      ]
    }
  },
  computed: {
    allChecked: {
      // 小选影响全选
      get () {
        return this.arr.every((item) => item.checked)
      },
      // 全选影响小选
      set (newVal) {
        this.arr.forEach(item => {
          item.checked = newVal
        })
      }
    }
  }
}
</script>