如何将siteMapNode节点默认为收缩状态

[救命啊啊]

<?xml version="1.0" encoding="utf-8" ?>
<siteMapNode title="系统" url="#" description="" target="" image="~/images/desk.gif">
<siteMapNode title="系统管理" url="#" description="" target="" image="~/images/t2.gif">
<siteMapNode title="考勤日期" url="~/super/setdata.aspx" description="" target="mainFrame" image="~/images/t5.gif"/>
<siteMapNode title="部门设置" url="~/super/deptadd.aspx" description="" target="mainFrame" image="~/images/t5.gif"/>
<siteMapNode title="课室设置" url="~/super/classadd.aspx" description="" target="mainFrame" image="~/images/t5.gif"/>
<siteMapNode title="登录管理" url="~/super/qxgl.aspx" description="" target="mainFrame" image="~/images/t5.gif"/>
</siteMapNode>
</siteMapNode>

一直是处于展开状态，如何将节点默认为收缩状态

<td height="700" style="vertical-align:top">
<asp:TreeView ID="TreeView1" runat="server" DataSourceID="xmlDs" NodeStyle-Height="23px" >
<DataBindings>
<asp:TreeNodeBinding DataMember="siteMapNode" ImageUrlField="image"
NavigateUrlField="url" TargetField="target" TextField="title" />
</DataBindings>
</asp:TreeView>
</td>

[csdn_aspnet]

http://www.cnblogs.com/30ErLi/archive/2010/09/17/1828962.html