zTree获取（子）节点

 var ids=[];
 ids=getChildren(ids, treeNode);//TreeNode是选中节点，ids是子节点id数组，格式：123,223,4,55

1.获取直接子节点的id

//返回值包含选中节点的id，即ids[0]
function getChildren(ids, treeNode) {
   ids.push(treeNode.id);//选中节点id，即父节点id
   if (treeNode.isParent) {
       for (var obj in treeNode.children) {
            getChildren(ids, treeNode.children[obj]);
       }
   }
   return ids;
}

2.获取全部子节点id

 //返回值是否包含选中节点id，根据情况而定
 function getChildren(ids, treeNode) {
    ids.push(treeNode.id);//选中节点id，即父节点id
    if (treeNode.isParent) {
        for (var obj in treeNode.children) {
             ids.push(treeNode.children[obj].id);
        }
    }
    return ids;
 }

3.获取某节点的所有子节点

 function getChildrenNodes(nodes, treeNode) {
    nodes.push(treeNode);
    if (treeNode.isParent) {
         for(var obj in treeNode.children) {
             getChildrenNodes(nodes, treeNode.children[obj]);
         }
    }
    return nodes;
 }

4.获取zTree的全部节点

 var nodes = [];
 var treeObj = $.fn.zTree.getZTreeObj("treeDemo");//zTree对象
 var roots = treeObj.getNodes(); //所有一级节点
 for (var i = ; i < roots.length; i++) {
     nodes = getChildrenNodes(nodes, roots[i]);
 }