zTree如何只取子节点的id值

zTree如何只取子节点的id值，目前项目中不需要取父节点的值，如何取得所有的子节点的值？

1.获取当前节点
2.用ztree的方法transformToArray()获取当前选中节点（含选中节点）的子节点对象集合。
3.遍历集合，取出需要的值。
function getChildNodes(treeNode) {
var childNodes = ztree.transformToArray(treeNode);
var nodes = new Array();
for(i = 0; i < childNodes.length; i++) {
nodes[i] = childNodes[i].id;
}
return nodes.join(",");
}

判断节点的isParent属性，为true就是父节点，否则子节点，再获取值

 var treeObj = $.fn.zTree.getZTreeObj("tree");
var nodes = treeObj.getNodes();//获取所有节点      treeObj.getSelectedNodes();//获取选中的节点
for(var i=0,j=nodes.length;i<j;i++)
if(!nodes[i].isParent)alert('子节点：'+nodes[i].name)

对所有节点遍历，，然后判断if(!node.isParent){console.log(node.id)}就可以了

已经解决了，附上实例。。。感谢各位大神，还有一个问题，zTree怎么赋值呢？比如说我现在存在数据库的值是211,111，不通过JSON怎么赋值到ZTree呢？

 <SCRIPT type="text/javascript">
        <!--
        var setting = {
            check: {
                enable: true
            },
            data: {
                simpleData: {
                    enable: true
                }
            },
             callback: { 

        onCheck:onCheck
    } 
        };

        var zNodes =[
            { id:1, pId:0, name:"随意勾选 1", open:true},
            { id:11, pId:1, name:"随意勾选 1-1", open:true},
            { id:111, pId:11, name:"随意勾选 1-1-1"},
            { id:112, pId:11, name:"随意勾选 1-1-2"},
            { id:12, pId:1, name:"随意勾选 1-2", open:true},
            { id:121, pId:12, name:"随意勾选 1-2-1"},
            { id:122, pId:12, name:"随意勾选 1-2-2"},
            { id:2, pId:0, name:"随意勾选 2", checked:true, open:true},
            { id:21, pId:2, name:"随意勾选 2-1"},
            { id:22, pId:2, name:"随意勾选 2-2", open:true},
            { id:221, pId:22, name:"随意勾选 2-2-1", checked:true},
            { id:222, pId:22, name:"随意勾选 2-2-2"},
            { id:23, pId:2, name:"随意勾选 2-3"}
        ];

        var code;

        function setCheck() {
            var zTree = $.fn.zTree.getZTreeObj("treeDemo"),
            py = $("#py").attr("checked")? "p":"",
            sy = $("#sy").attr("checked")? "s":"",
            pn = $("#pn").attr("checked")? "p":"",
            sn = $("#sn").attr("checked")? "s":"",
            type = { "Y":py + sy, "N":pn + sn};
            zTree.setting.check.chkboxType = type;
            showCode('setting.check.chkboxType = { "Y" : "' + type.Y + '", "N" : "' + type.N + '" };');
        }
        function showCode(str) {
            if (!code) code = $("#code");
            code.empty();
            code.append("<li>"+str+"</li>");
        }

        $(document).ready(function(){
            $.fn.zTree.init($("#treeDemo"), setting, zNodes);
            setCheck();
            $("#py").bind("change", setCheck);
            $("#sy").bind("change", setCheck);
            $("#pn").bind("change", setCheck);
            $("#sn").bind("change", setCheck);
        });

        function onCheck(e, treeId, treeNode) {
　 var zTree = $.fn.zTree.getZTreeObj("treeDemo"),
　 nodes = zTree.getCheckedNodes(true),
　 v = "";
　 for (var i=0, l=nodes.length; i<l; i++) {
if(!nodes[i].isParent){
　　v += nodes[i].id + ",";
}
　　
　 }
alert(v);　 //获取选中子节点的id值
        //-->

    </SCRIPT>