vue element-ui tree 根节点固定子节点懒加载 首次加载根节点并展开

关键代码：

  <el-tree ref="foldTree" node-key="id" :highlight-current="true" :props="defaultProps" lazy :load="handLoadNode" @node-click="handleNodeClick" />

　　

data() {
    return {
      CurrentNode: null,
      CurrentNodeResolve: null,
      RootNode: { id: "000", Name: "根目录", Path: "" },
    }
  },

　　

mounted() {
    var _rNode = this.CurrentNode.childNodes[0];
    _rNode.checked = true;
    _rNode.expanded = true;
    _rNode.loadData();
  }

　　

 handLoadNode(node, resolve) {
      this.CurrentNodeResolve = resolve;
      this.CurrentNode = node;
      if (node.level === 0) {
        return resolve([this.RootNode]);
      } else {
        ...
        }
}