如果el-tree自定义节点包含el-dropdown，为了防止点击el-dropdown的触发按钮而执行el-tree的node-click事件
最外层添加div，给div绑定事件并添加事件修饰符（stop）
<el-tree :data="treeData" @node-click="treeNodeClickEvent"><div @click.stop><el-dropdown trigger="click"><span class="el-dropdown-link"><i class="el-icon-more"></i></span><el-dropdown-menu slot="dropdown"><el-dropdown-item><i class="my-icon icon-folder"></i><span>创建文件夹</span></el-dropdown-item><el-dropdown-item><i class="my-icon icon-document"></i><span>创建文档</span></el-dropdown-item><el-dropdown-item><i class="my-icon icon-markdown"></i><span>创建Markdown</span></el-dropdown-item><el-dropdown-item><i class="my-icon icon-edit"></i><span>编辑</span></el-dropdown-item><el-dropdown-item><i class="my-icon icon-delete"></i><span>删除</span></el-dropdown-item></el-dropdown-menu></el-dropdown></div>
</el-tree>
参考：
ElementUI dropdown 触发显示时阻止事件冒泡