ElementUI浅尝辄止35：Checkbox 多选框

一组备选项中进行多选 

1.如何使用？

单独使用可以表示两种状态之间的切换，写在标签中的内容为 checkbox 按钮后的介绍。

//在el-checkbox元素中定义v-model绑定变量，单一的checkbox中，默认绑定变量的值会是Boolean，选中为true。<template><!-- `checked` 为 true 或 false --><el-checkbox v-model="checked">备选项</el-checkbox>
</template>
<script>export default {data() {return {checked: true};}};
</script>

2.禁用状态

多选框不可用状态。

设置disabled属性即可。<template><el-checkbox v-model="checked1" disabled>备选项1</el-checkbox><el-checkbox v-model="checked2" disabled>备选项</el-checkbox>
</template>
<script>export default {data() {return {checked1: false,checked2: true};}};
</script>

3.多选框组

适用于多个勾选框绑定到同一个数组的情景，通过是否勾选来表示这一组选项中选中的项。

/*checkbox-group元素能把多个 checkbox 管理为一组，只需要在 Group 中使用v-model绑定Array类型的变量即可。 el-checkbox 的 label属性是该 checkbox 对应的值，若该标签中无内容，则该属性也充当 checkbox 按钮后的介绍。label与数组中的元素值相对应，如果存在指定的值则为选中状态，否则为不选中。*/<template><el-checkbox-group v-model="checkList"><el-checkbox label="复选框 A"></el-checkbox><el-checkbox label="复选框 B"></el-checkbox><el-checkbox label="复选框 C"></el-checkbox><el-checkbox label="禁用" disabled></el-checkbox><el-checkbox label="选中且禁用" disabled></el-checkbox></el-checkbox-group>
</template><script>export default {data () {return {checkList: ['选中且禁用','复选框 A']};}};
</script>

4.indeterminate 状态

indeterminate 属性用以表示 checkbox 的不确定状态，一般用于实现全选的效果

<template><el-checkbox :indeterminate="isIndeterminate" v-model="checkAll" @change="handleCheckAllChange">全选</el-checkbox><div style="margin: 15px 0;"></div><el-checkbox-group v-model="checkedCities" @change="handleCheckedCitiesChange"><el-checkbox v-for="city in cities" :label="city" :key="city">{{city}}</el-checkbox></el-checkbox-group>
</template>
<script>const cityOptions = ['上海', '北京', '广州', '深圳'];export default {data() {return {checkAll: false,checkedCities: ['上海', '北京'],cities: cityOptions,isIndeterminate: true};},methods: {handleCheckAllChange(val) {this.checkedCities = val ? cityOptions : [];this.isIndeterminate = false;},handleCheckedCitiesChange(value) {let checkedCount = value.length;this.checkAll = checkedCount === this.cities.length;this.isIndeterminate = checkedCount > 0 && checkedCount < this.cities.length;}}};
</script>

5.可选项目数量的限制

使用 min 和 max 属性能够限制可以被勾选的项目的数量。

<template><el-checkbox-group v-model="checkedCities":min="1":max="2"><el-checkbox v-for="city in cities" :label="city" :key="city">{{city}}</el-checkbox></el-checkbox-group>
</template>
<script>const cityOptions = ['上海', '北京', '广州', '深圳'];export default {data() {return {checkedCities: ['上海', '北京'],cities: cityOptions};}};
</script>

6.按钮样式

按钮样式的多选组合。

<template><div><el-checkbox-group v-model="checkboxGroup1"><el-checkbox-button v-for="city in cities" :label="city" :key="city">{{city}}</el-checkbox-button></el-checkbox-group></div><div style="margin-top: 20px"><el-checkbox-group v-model="checkboxGroup2" size="medium"><el-checkbox-button v-for="city in cities" :label="city" :key="city">{{city}}</el-checkbox-button></el-checkbox-group></div><div style="margin-top: 20px"><el-checkbox-group v-model="checkboxGroup3" size="small"><el-checkbox-button v-for="city in cities" :label="city" :disabled="city === '北京'" :key="city">{{city}}</el-checkbox-button></el-checkbox-group></div><div style="margin-top: 20px"><el-checkbox-group v-model="checkboxGroup4" size="mini" disabled><el-checkbox-button v-for="city in cities" :label="city" :key="city">{{city}}</el-checkbox-button></el-checkbox-group></div>
</template>
<script>const cityOptions = ['上海', '北京', '广州', '深圳'];export default {data () {return {checkboxGroup1: ['上海'],checkboxGroup2: ['上海'],checkboxGroup3: ['上海'],checkboxGroup4: ['上海'],cities: cityOptions};}}
</script>

7.带有边框

设置border属性可以渲染为带有边框的多选框。<template><div><el-checkbox v-model="checked1" label="备选项1" border></el-checkbox><el-checkbox v-model="checked2" label="备选项2" border></el-checkbox></div><div style="margin-top: 20px"><el-checkbox v-model="checked3" label="备选项1" border size="medium"></el-checkbox><el-checkbox v-model="checked4" label="备选项2" border size="medium"></el-checkbox></div><div style="margin-top: 20px"><el-checkbox-group v-model="checkboxGroup1" size="small"><el-checkbox label="备选项1" border></el-checkbox><el-checkbox label="备选项2" border disabled></el-checkbox></el-checkbox-group></div><div style="margin-top: 20px"><el-checkbox-group v-model="checkboxGroup2" size="mini" disabled><el-checkbox label="备选项1" border></el-checkbox><el-checkbox label="备选项2" border></el-checkbox></el-checkbox-group></div>
</template><script>export default {data () {return {checked1: true,checked2: false,checked3: false,checked4: true,checkboxGroup1: [],checkboxGroup2: []};}}
</script>