el-autocomplete 自动补全组件

自补全组件的功能和可以根据输入过滤的el-select组件有些类似。

fetch-suggestions 根据输入框的输入获取建议的内容，其接受值是一个函数，有2个参数，querystring:输入的内容，callback内置函数，将结果传入callback中完成渲染。

<script setup lang="ts">
import { onMounted, ref } from 'vue'

interface RestaurantItem {
  value: string
  link: string
}

const state = ref('')

const restaurants = ref<RestaurantItem[]>([])
const querySearch = (queryString: string, cb: any) => {
  const results = queryString
    ? restaurants.value.filter(createFilter(queryString))
    : restaurants.value
  // call callback function to return suggestions
  cb(results)
}
const createFilter = (queryString: string) => {
  return (restaurant: RestaurantItem) => {
    return (
      restaurant.value.toLowerCase().indexOf(queryString.toLowerCase()) === 0
    )
  }
}
//子元素属性必须包含value
const loadAll = () => {
  return [
    { value: 'vue', link: 'https://github.com/vuejs/vue' },
    { value: 'element', link: 'https://github.com/ElemeFE/element' },
    { value: 'cooking', link: 'https://github.com/ElemeFE/cooking' },
    { value: 'mint-ui', link: 'https://github.com/ElemeFE/mint-ui' },
    { value: 'vuex', link: 'https://github.com/vuejs/vuex' },
    { value: 'vue-router', link: 'https://github.com/vuejs/vue-router' },
    { value: 'babel', link: 'https://github.com/babel/babel' },
  ]
}

const handleSelect = (item: RestaurantItem) => {
  console.log(item)
}

onMounted(() => {
  restaurants.value = loadAll()
})
 


const handleChange=(value)=>{
    console.log(value)
}

const props={
    expandTrigger:'hover'
}

</script>

    
<template>
  <div>
    <el-row>
    <el-autocomplete
        v-model="state"
        :fetch-suggestions="querySearch"
        clearable
        @select="handleSelect"
        placeholder="please input"
      ></el-autocomplete>
    </el-row>
   
  </div>
      
</template>

<style scoped>
    .container{
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-content: center;
    }

    .item{
      background-color: lightskyblue;
      margin:10px 10px;
      text-align: center;
      border: 1px solid black;
    }

</style>

2.el-cascader 级联选择器

级联选择器适用于带层级结构的筛选项。该组件支持多选，禁用，多级嵌套，内置多种事件等特性。
如下

<script setup lang="ts">
import { onMounted, ref } from 'vue'

class OptionItem{
  label:string
  value:string
  children:OptionItem[]
  disabled:boolean

  constructor(label:string,value:string,children:OptionItem[],disabled:boolean){
      this.label=label
      this.value=value
      this.children=children
      this.disabled=disabled
  }
}

const region = ref('');

const region2 = ref('');
const options = ref(<OptionItem[]>[{
  label:"hunan",
  value:"hunan",
  disabled:false,
  children:[{
    label:"changsha",
    value:"changsha",
    disabled:false,
    children:[{
        label:"tianixinqu",
        value:"tianxinqu",
        disabled:false,
        children:[]
    },{
        label:"furongqu",
        value:"furongqu",
        children:[]
    },{
        label:"yuhuaqu",
        value:"yuhuaqu",
        children:[]
    }]
},{
    label:"zhuzhou",
    value:"zhuzhou",
    disabled:true,
    children:[{
        label:"haizhuqu",
        value:"haizhuqu",
        children:[]
    }]
  },{
    label:"xiangtan",
    value:"xiangtan",
    children:[{
      
    }]
  }

]}]);


const handleChange=(value)=>{
    console.log(value)
}

const props={
    expandTrigger:'hover'
}

</script>

    
<template>
  <div>
    <el-row>
    <el-autocomplete
        v-model="state"
        :fetch-suggestions="querySearch"
        clearable
        @select="handleSelect"
        placeholder="please input"
      ></el-autocomplete>
    </el-row>
   


      
      <el-row>
        <el-col :span="8">
          <el-cascader v-model="region" :options="options" @change="handleChange" :props="props"
      ></el-cascader>
        </el-col>
      
      <el-col :span="8">
        <el-cascader v-model="region2" :options="options" @change="handleChange" :props="props"
      ></el-cascader>
      </el-col>
     
    </el-row>
  </div>
      
</template>

<style scoped>
    .container{
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-content: center;
    }

    .item{
      background-color: lightskyblue;
      margin:10px 10px;
      text-align: center;
      border: 1px solid black;
    }

</style>

https://element-plus.org/zh-CN/component/cascader.html#cascader-api