用element-plus+vue3+ts实现搜索下拉框

<template>
	<div class="search_select_body">
		<el-select
			v-model="currentOption"
			placeholder="请选择"
			popper-class="select_box"
			:multiple="multipleOpt"
			@change="changeSelect"
			@visible-change="showOrHidden"
			@remove-tag="removeTag"
		>
			<div class="search_input_box">
				<el-input v-model="searchKey" placeholder="请输入搜索内容" @input="confirmSearch" />
			div>
			<el-option v-for="(item, index) in memberOption" :key="index" :label="item.name" :value="item.id"
				><span v-if="item.id" class="diy_check">span>{{ item.displayname }}el-option
			>
		el-select>
	div>
template>

<script lang="ts">
import { defineComponent, toRefs, reactive, computed, toRef, ref } from 'vue';
interface Idata {
	optionData: any[];
	multipleOpt: boolean;
}
interface Ioption {
//这里要看你要传进来的是什么数据，根据实际情况而定
	name: string;
	id: string;
}

export default defineComponent({
	props: {
		optionData: {
			type: Array,
			default() {
				return [];
			},
			require: true,
		},
		multipleOpt: {
			type: Boolean,
			default: true,
			require: true,
		},
	},
	emits: ['deliverVal', 'deliverKeyword'],
	//默认值和重置在父组件中用ref来设置
	setup(props: Idata, context) {
		const state = reactive({
			searchKey: '',   //搜索框输入的值
		});
		let currentOption: any = ref([]);  //选中的值，单选为字符串，多选为数组
		const confirmSearch = (val: string | number) => {
			if (val !== '') {
				context.emit('deliverKeyword', val.toString());
			}
		};
		const { optionData, multipleOpt } = toRefs(props);
		if (!multipleOpt.value) {
			currentOption.value = '';
		}
		const memberOption = computed(() => {
		//选项值根据父组件传过来的值进行属性计算得出，这里因为业务需求写的复杂了些，可根据你的实际情况而修改
			let searchOption = [] as Ioption[];
			if (optionData.value.length) {
				optionData.value.forEach((item: any) => {
					searchOption.push({
						name: item.displayname,
						id: item.id,
					});
				});
			}
			return searchOption.length ? searchOption : [''];     //无论单选还是多选，这里需要一个默认的空值来控制输入框显示（element-plus的el-select组件只有有值才能渲染el-select标签内部的dom节点）
		});
		const changeSelect = (val: string[] | string) => {
			if (memberOption.value.length == 1 && memberOption.value[0] == '') {
				currentOption.value = multipleOpt.value ? [] : '';     //选第一个空值的时候做的处理
			}
		};
		const showOrHidden = (val: boolean) => {
			if (!val) {
				//多选遍历后传值，单选直接传选中值
				if (multipleOpt.value) {
					multiChangeVal();
				} else {
					context.emit('deliverVal', currentOption.value);
				}
			}
		};
		const removeTag = () => {
			//此方法主要是给父组件用，用于删除选项时再次把最新的值传给父组件
			multiChangeVal();
		};
		const multiChangeVal = () => {
		//多选的时将值传给父组件
			let result = [] as any[];
			memberOption.value.forEach((item: any) => {
				currentOption.value.forEach((items: string) => {
					if (items === item.id) {
						result.push({
							name: item.displayname,
							id: item.id,
						});
					}
				});
			});
			context.emit('deliverVal', result);
		};
		return {
			confirmSearch,
			...toRefs(state),
			memberOption,
			changeSelect,
			showOrHidden,
			currentOption,
			removeTag,
		};
	},
});
script>
<style scoped lang="less">
.search_select_body {
	position: relative;
	.search_input_box {
		position: absolute;
		top: 44px;
		left: 0;
		z-index: 3000;
	}
}
style>