xml文件绑定到DataList的问题！ - .NET技术 / C#

XML文件结构如下:
<?xml version="1.0" standalone="yes"?>
<NewDataSet>
  <Table>
  <productID>1</productID>
  <productname>S200</productname>
  <productdescription />
  <originalprice>2100.0000</originalprice>
  <saleprice>2000.0000</saleprice>
  <categoryID>2</categoryID>
  <photo>S200.jpg</photo>
  <publishyear>2007</publishyear>
  <publishmonth>4</publishmonth>
  </Table>
  <Table>
  <productID>2</productID>
  <productname>S500</productname>
  <originalprice>2500.0000</originalprice>
  <saleprice>2320.0000</saleprice>
  <categoryID>2</categoryID>
  <photo>S500.jpg</photo>
  <publishyear>2007</publishyear>
  <publishmonth>3</publishmonth>
  </Table>
  <Table>
  <productID>3</productID>
  <productname>S50</productname>
  <originalprice>2030.0000</originalprice>
  <saleprice>1950.0000</saleprice>
  <categoryID>2</categor