需求：
领导看我在另一个vue3项目的el-tree-select挺好的，叫我移入vue2的项目中。
但是vue2版本的elementUI，并没有这个组件，所以只能自己找，找半天找不到和它差不多的，通过网友写的组件改写的
参考链接：
利用 el-select 和 el-tree 实现树形结构多选框联动功能
组件示例照片：
使用：
<elTreeSelect
:props="{
value: 'id',
label: 'label',
children: 'children',
}"
:options="deptOptions"
:value="deptId"
:clearable="false"
:accordion="true"
@getValue="handleNodeClick"
height="200"
/>
data() {
return {
deptId: '', // 牧场id
deptOptions: [
{
"id": 201,
"label": "突泉县",
"children": [
{
"id": 202,
"label": "东杜尔基镇",
"children": [
{
"id": 12,
"label": "东方镜养殖户",
"farmFlag": "1",
"level": null
}
],
"farmFlag": null,
"level": "4"
},
{
"id": 203,
"label": "六户镇",
"children": [
{
"id": 14,
"label": "澜养殖户",
"farmFlag": "1",
"level": null
}
],
"farmFlag": null,
"level": "4"
},
{
"id": 204,
"label": "永安镇",
"farmFlag": null,
"level": "4"
},
{
"id": 205,
"label": "学田乡",
"farmFlag": null,
"level": "4"
},
{
"id": 206,
"label": "宝石镇",
"children": [
{
"id": 3,
"label": "张三养殖户",
"farmFlag": "1",
"level": null
}
],
"farmFlag": null,
"level": "4"
},
{
"id": 207,
"label": "太平乡",
"farmFlag": null,
"level": "4"
},
{
"id": 208,
"label": "突泉镇",
"farmFlag": null,
"level": "4"
},
{
"id": 209,
"label": "水泉镇",
"farmFlag": null,
"level": "4"
},
{
"id": 210,
"label": "内蒙古自治区国营杜尔基农场",
"farmFlag": null,
"level": "4"
},
{
"id": 211,
"label": "九龙乡",
"farmFlag": null,
"level": "4"
}
],
"farmFlag": null,
"level": "3"
}
], // tree数据
},
methods: {
// 节点单击事件
handleNodeClick(data) {
console.log('选择的数据', data);
}
}
组件代码：
<template>
<el-select
v-model="valueTitle"
:clearable="clearable"
@clear="clearHandle"
ref="treeSelect"
filterable
:filter-method="filterSelect"
@visible-change="clearSelect"
placeholder="请选择"
>
<!-- <el-input
class="selectInput"
:placeholder="placeholder"
v-model="filterText"
>
</el-input> -->
<el-option :value="valueTitle" :label="valueTitle" class="options">
<el-tree
id="tree-option"
ref="selectTree"
:accordion="accordion"
:data="treeOptions"
:props="props"
:node-key="props.value"
:default-expanded-keys="defaultExpandedKey"
:filter-node-method="filterNode"
@node-click="handleNodeClick"
>
</el-tree>
</el-option>
</el-select>
</template>
<script>
export default {
name: "el-tree-select",
props: {
/* 配置项 */
props: {
type: Object,
default: () => {
return {
value: "id", // ID字段名
label: "title", // 显示名称
children: "children", // 子级字段名
};
},
},
/* 选项列表数据(树形结构的对象数组) */
options: {
type: Array,
default: () => {
return [];
},
},
/* 初始值 */
value: {
type: Number | String,
default: () => {
return null;
},
},
/* 可清空选项 */
clearable: {
type: Boolean,
default: () => {
return true;
},
},
/* 自动收起 */
accordion: {
type: Boolean,
default: () => {
return false;
},
},
placeholder: {
type: String,
default: () => {
return "检索关键字";
},
},
},
data() {
return {
filterText: "",
valueId: this.value, // 初始值
valueTitle: "",
defaultExpandedKey: [],
treeOptions: [],
};
},
mounted() {
this.initHandle();
},
methods: {
// 初始化值
initHandle() {
if (this.valueId && this.options && this.options.length > 0) {
let info = this.findFirstDeptFarm2(this.options);
this.valueTitle = info.label; // 初始化显示
// this.$refs.selectTree.getNode(this.valueId).data[this.props.label]
this.$refs.selectTree.setCurrentKey(this.valueId); // 设置默认选中
this.defaultExpandedKey = [this.valueId]; // 设置默认展开
this.treeOptions = this.options;
}
this.initScroll();
},
// 初始化滚动条
initScroll() {
this.$nextTick(() => {
let scrollWrap = document.querySelectorAll(
".el-scrollbar .el-select-dropdown__wrap"
)[0];
let scrollBar = document.querySelectorAll(
".el-scrollbar .el-scrollbar__bar"
);
scrollWrap.style.cssText =
"margin: 0px; max-height: none; overflow: hidden;";
scrollBar.forEach((ele) => (ele.style.width = 0));
});
},
// 切换选项
handleNodeClick(node) {
this.valueTitle = node[this.props.label];
this.valueId = node[this.props.value];
this.$emit("getValue", {
id: this.valueId,
label: this.valueTitle,
farmFlag: node.farmFlag,
});
this.defaultExpandedKey = [];
// if (!node.children || !node.children.length) {
//补录选择完选项弹框不能收起
this.$refs.treeSelect.blur();
// }
},
// 清除选中
clearHandle() {
this.valueTitle = "";
this.valueId = null;
this.defaultExpandedKey = [];
this.clearSelected();
this.$emit("getValue", null);
},
/* 清空选中样式 */
clearSelected() {
let allNode = document.querySelectorAll("#tree-option .el-tree-node");
allNode.forEach((element) => element.classList.remove("is-current"));
},
filterNode(value, data) {
if (!value) return true;
return data.name.indexOf(value) !== -1;
},
findFirstDeptFarm2(arr) {
for (let i = 0; i < arr.length; i++) {
if (arr[i].id === this.valueId) {
return arr[i];
} else if (
Array.isArray(arr[i].children) &&
arr[i].children.length > 0
) {
const result = this.findFirstDeptFarm2(arr[i].children);
if (result) {
return result;
}
}
}
return null;
},
clearSelect(show) {
if (!show) {
this.treeOptions = this.options;
}
},
filterSelect(val) {
if (val) {
this.treeOptions = this.filterTreeByName(this.options, val);
} else {
this.treeOptions = this.options;
}
},
filterTreeByName(tree, nameToMatch) {
// 递归函数，用于遍历树并找到匹配的节点及其父节点
function traverseAndFilter(node, filteredTree = []) {
// 如果节点的name匹配，则将其添加到filteredTree中
if (node.label.indexOf(nameToMatch) !== -1) {
filteredTree.push(node);
}
// 遍历节点的子节点
if (node.children) {
for (let child of node.children) {
// 递归调用traverseAndFilter来检查子节点
traverseAndFilter(child, filteredTree);
}
}
// 如果filteredTree不为空，说明找到了匹配项，返回filteredTree
// 否则返回null，表示当前节点及其子节点中都没有匹配项
return filteredTree.length ? filteredTree : null;
}
// 初始化结果树
let resultTree = [];
// 遍历树的根节点
for (let rootNode of tree) {
let filteredNodes = traverseAndFilter(rootNode);
// 如果filteredNodes不为空，说明找到了匹配项，将其添加到结果树中
if (filteredNodes) {
resultTree = resultTree.concat(filteredNodes);
}
}
// 去除重复的节点（如果有的话），因为可能通过多个路径找到了相同的节点
resultTree = [
...new Map(resultTree.map((node) => [node.id || node, node])).values(),
];
// 如果没有找到任何匹配的节点，返回null
if (resultTree.length === 0) {
return null;
}
// 构建最终的树形结构，只包含匹配的节点及其父节点
function buildFilteredTree(nodes) {
const filteredTree = [];
const nodeMap = new Map();
for (const node of nodes) {
nodeMap.set(node.id || node, node);
}
for (const node of nodes) {
const parent = node.parent;
if (!parent || nodeMap.has(parent)) {
let currentNode = nodeMap.get(node.id || node);
let parentNode = parent ? nodeMap.get(parent) : null;
if (parentNode) {
if (!parentNode.children) {
parentNode.children = [];
}
parentNode.children.push(currentNode);
filteredTree.push(parentNode);
} else {
filteredTree.push(currentNode);
}
}
}
return filteredTree;
}
// 如果找到了匹配的节点，则构建最终的树形结构
if (resultTree.length > 0) {
return buildFilteredTree(resultTree);
}
// 如果没有找到匹配的节点，返回null
return null;
},
},
watch: {
value() {
this.valueId = this.value;
this.initHandle();
},
filterText(val) {
if (val) {
try {
this.$refs.selectTree.filter(val);
} catch (error) {}
}
},
},
};
</script>
<!-- Add "scoped" attribute to limit CSS to this component only -->
<style scoped>
.el-scrollbar .el-scrollbar__view .el-select-dropdown__item {
height: auto;
max-height: 274px;
padding: 0;
overflow: hidden;
overflow-y: auto;
}
.el-select-dropdown__item.selected {
font-weight: normal;
}
ul li >>> .el-tree .el-tree-node__content {
height: auto;
padding: 0 20px;
}
.el-tree-node__label {
font-weight: normal;
}
.el-tree >>> .is-current .el-tree-node__label {
color: #409eff;
font-weight: 700;
}
.el-tree >>> .is-current .el-tree-node__children .el-tree-node__label {
color: #606266;
font-weight: normal;
}
.selectInput {
padding: 0 5px;
box-sizing: border-box;
}
</style>
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