ZTree中按节点层次展开树节点的方法
function expandLevel(treeObj,node,level){var childrenNodes = node.children;for(var i=0;i<childrenNodes.length;i++){treeObj.expandNode(childrenNodes[i], true, false, false);level=level-1;if(level>0){expandLevel(treeObj,childrenNodes[i],level);}}}

?调用方法：

var rootNode=zMenuTree.getNodes()[0];expandLevel(zMenuTree,rootNode,1);

?