ant-design-vue/components/select/demo/optgroup.md

#### 分组 用 `OptGroup` 进行选项分组。 #### Option Group Using `OptGroup` to group the options.

<template>
  <a-select defaultValue="lucy" style="width: 200px" @change="handleChange">
    <a-select-opt-group>
      <span slot="label"><a-icon type="user"/>Manager</span>
      <a-select-option value="jack">Jack</a-select-option>
      <a-select-option value="lucy">Lucy</a-select-option>
    </a-select-opt-group>
    <a-select-opt-group label="Engineer">
      <a-select-option value="Yiminghe">yiminghe</a-select-option>
    </a-select-opt-group>
  </a-select>
</template>
<script>
export default {
  methods: {
    handleChange(value) {
      console.log(`selected ${value}`);
    }
  }
}
</script>