vue全选实现

Vue 全选实现方法

在 Vue 中实现全选功能通常涉及数据绑定和事件处理。以下是几种常见的实现方式：

基础实现方式

<template>
  <div>
    <input type="checkbox" v-model="selectAll" @change="toggleAll"> 全选
    <div v-for="item in items" :key="item.id">
      <input type="checkbox" v-model="selectedItems" :value="item.id">
      {{ item.name }}
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      items: [
        { id: 1, name: '选项1' },
        { id: 2, name: '选项2' },
        { id: 3, name: '选项3' }
      ],
      selectedItems: [],
      selectAll: false
    }
  },
  methods: {
    toggleAll() {
      if (this.selectAll) {
        this.selectedItems = this.items.map(item => item.id)
      } else {
        this.selectedItems = []
      }
    }
  },
  watch: {
    selectedItems(newVal) {
      this.selectAll = newVal.length === this.items.length
    }
  }
}
</script>

使用计算属性优化

<template>
  <div>
    <input type="checkbox" v-model="selectAll"> 全选
    <div v-for="item in items" :key="item.id">
      <input type="checkbox" v-model="selectedItems" :value="item.id">
      {{ item.name }}
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      items: [
        { id: 1, name: '选项1' },
        { id: 2, name: '选项2' },
        { id: 3, name: '选项3' }
      ],
      selectedItems: []
    }
  },
  computed: {
    selectAll: {
      get() {
        return this.selectedItems.length === this.items.length
      },
      set(value) {
        this.selectedItems = value ? this.items.map(item => item.id) : []
      }
    }
  }
}
</script>

表格中的全选实现

<template>
  <table>
    <thead>
      <tr>
        <th><input type="checkbox" v-model="selectAll"></th>
        <th>名称</th>
        <th>价格</th>
      </tr>
    </thead>
    <tbody>
      <tr v-for="item in items" :key="item.id">
        <td><input type="checkbox" v-model="selectedItems" :value="item.id"></td>
        <td>{{ item.name }}</td>
        <td>{{ item.price }}</td>
      </tr>
    </tbody>
  </table>
</template>

<script>
export default {
  data() {
    return {
      items: [
        { id: 1, name: '商品1', price: 100 },
        { id: 2, name: '商品2', price: 200 },
        { id: 3, name: '商品3', price: 300 }
      ],
      selectedItems: []
    }
  },
  computed: {
    selectAll: {
      get() {
        return this.selectedItems.length === this.items.length
      },
      set(value) {
        this.selectedItems = value ? this.items.map(item => item.id) : []
      }
    }
  }
}
</script>

使用 Vuex 管理状态

// store.js
export default new Vuex.Store({
  state: {
    items: [
      { id: 1, name: '选项1' },
      { id: 2, name: '选项2' },
      { id: 3, name: '选项3' }
    ],
    selectedItems: []
  },
  mutations: {
    toggleAll(state, payload) {
      state.selectedItems = payload ? state.items.map(item => item.id) : []
    },
    updateSelectedItems(state, payload) {
      state.selectedItems = payload
    }
  },
  getters: {
    selectAll: state => {
      return state.selectedItems.length === state.items.length
    }
  }
})

<!-- Component.vue -->
<template>
  <div>
    <input type="checkbox" 
           :checked="selectAll" 
           @change="$store.commit('toggleAll', $event.target.checked)">
    全选
    <div v-for="item in items" :key="item.id">
      <input type="checkbox" 
             :value="item.id" 
             :checked="selectedItems.includes(item.id)"
             @change="updateSelection">
      {{ item.name }}
    </div>
  </div>
</template>

<script>
import { mapState, mapGetters } from 'vuex'

export default {
  computed: {
    ...mapState(['items', 'selectedItems']),
    ...mapGetters(['selectAll'])
  },
  methods: {
    updateSelection(e) {
      const id = Number(e.target.value)
      let newSelected = [...this.selectedItems]

      if (e.target.checked) {
        newSelected.push(id)
      } else {
        newSelected = newSelected.filter(item => item !== id)
      }

      this.$store.commit('updateSelectedItems', newSelected)
    }
  }
}
</script>

以上方法涵盖了 Vue 中实现全选功能的主要方式，可以根据项目需求选择适合的方案。计算属性方式通常更为简洁高效，而 Vuex 方案则适合大型应用中的状态管理。