ztree中获取某节点的所有叶子节点

var setting = {
data: {
simpleData: {
enable: true
}
},
callback: {
onClick: treenodeClick
}
};

function treenodeClick(event, treeId, treeNode, clickFlag) {
//此处treeNode 为当前节点
var str ='' ;
str = getAllChildrenNodes(treeNode,str);
alert(str); //所有叶子节点ID
}

function getAllChildrenNodes(treeNode,result){
if (treeNode.isParent) {
var childrenNodes = treeNode.children;
if (childrenNodes) {
for (var i = 0; i < childrenNodes.length; i++) {
result += ',' + childrenNodes[i].id;
result = getChildNodes(childrenNodes[i], result);//使用递归，找到所有的子节点
}
}
}
return result;
}