从MSDN的例子是
System.IO.StringReader stream = new System.IO.StringReader(strXML);
System.Xml.XmlTextReader xr = new XmlTextReader(stream);
DataSet ds = new DataSet();
ds.ReadXml(xr);
这样好像很烦喔
(原例在这:http://chs.gotdotnet.com/quickstart/util/srcview.aspx?path=/quickstart/howto/samples/Xml/ReadXmlStream/ReadXmlStream.src&file=CS\ReadXmlStream.cs&font=3)