SPSiteDataQuery这东西可以返回DataTable
这东西可以查询某一类的list,也可以只查询某几个list
<Lists ServerTemplate=[value]/>
<Lists BaseType=[value]/>
<Webs Scope='SiteCollection' />
<Webs Scope='Recursive' />
<Lists> <List ID="7A9FDBE6-0841-430a-8D9A-53355801B5D5" /> <List ID="3D18F506-FCA1-451e-B645-2D720DC84FD8" /></Lists>
http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.spsitedataquery.lists.aspx#Y2084