Menu控件无法显示二级子菜单

url="Quotes.aspx" />
<siteMapNode title="Markets" description="The Latest Market Information"
url="Markets.aspx">
<siteMapNode title="U.S. Market Report"
description="Looking at the U.S. Market" url="MarketsUS.aspx" />
<siteMapNode title="NYSE"
description="The New York Stock Exchange" url="NYSE.aspx" />
</siteMapNode>
<siteMapNode title="Funds" description="Mutual Funds"
url="Funds.aspx" />
</siteMapNode>
<siteMapNode title="Weather" description="The Latest Weather"
url="Weather.aspx" />
</siteMapNode>
</siteMap>


求教啊！！！
[解决办法]
代码没问题吧
asp:Menu设置宽度和高度试试，比如100px