让UniDBTreeGrid默认展开一级节点：
function store.nodeappend(sender, node, index, eOpts) { if (node.raw.depth==1) { node.expand(); } }
原文地址：
http://forums.unigui.com/index.php?/topic/11740-how-to-expand-unidbtreegrid-first-level-nodes-programmatically/&tab=comments#comment-62357
默认让UniDBTreeGrid展开一级节点
原文：https://www.cnblogs.com/kinglandsoft/p/15171829.html
