1、需求描述：点击按钮切换树形的章节，同时高亮

2、代码实现
1）style样式添加

<style>
.el-tree--highlight-current .el-tree-node.is-current > .el-tree-node__content {background-color: #81d3f8 !important;  //高亮颜色color:#fff;  // 字体颜色
}
</style>```2）组件添加```javascript<el-treeref="treeRef"   :data="treeData"node-key="key"   //node-key必须要绑定唯一id，我这里的id是key所以使用key:highlight-current="true"  //设置高亮:default-expanded-keys="['0-1-0']"  // 默认展开@node-click="handleNodeClick"  // 节点点击事件></el-tree> 

3）事件

mounted(){this.$refs.treeRef.setCurrentKey(this.treeData[0].key);  //threeData是树形结构的数据//toNextClick是“下一步”按钮触发的事件this.$bus.$on("toNextClick", () => {this.getkey(this.treeData, this.componentsKey);  //this.componentsKey是当前的key//找到点击下一步之后的key值this.$refs.treeRef.setCurrentKey(this.keys); //添加高亮});
}

注：其他函数代码

// 寻找下一个key的位置getkey(obj, okey) {//找到okey在的位置let treeDataLen = this.treeData.length;let rootKey;let parentKey;let parentArrLen;let parentArr;let rootArr = this.treeData;if (!okey) {okey = "0-0";}let num = okey.match(/-/gim).length;if (num == 2) {//二级菜单rootKey = okey.slice(0, 3);parentKey = rootKey;} else if (num == 3) {rootKey = okey.slice(0, 5);parentKey = okey.slice(0, 3);} else {//直接去下一个rootKey = okey;parentKey = rootKey;}let rootindex = rootArr.map(item => item.key).indexOf(rootKey);//找到okey的上一级的children长度let parentObj = this.treeData.find(item => {return item.key == parentKey;});if (parentObj.key == "0-0") {if (rootindex + 1 < treeDataLen && rootArr[rootindex + 1].children) {this.str = rootArr[rootindex + 1].children[0].key;}return;} else {parentArr = parentObj.children ? parentObj.children : [];}//找到okey的下标parentArrLen = parentArr.length;let keyindex = parentArr.map(item => item.key).indexOf(okey);//根元素的下标if (keyindex + 1 > parentArrLen - 1 && rootindex + 1 >= treeDataLen) {this.str = okey;} else if (keyindex + 1 > parentArrLen - 1 &&rootindex + 1 < treeDataLen) {//子元素超出但是根还有if (rootArr[rootindex + 1].children) {this.str = rootArr[rootindex + 1].children[0].key;}} else {this.str = parentArr[keyindex + 1].key;}}}```