1 SqlConnection conn = new SqlConnection();
2       conn.ConnectionString = "Server=127.0.0.1;User ID=sa;Password=fdahgdrethj31313210212121;Database=northwind;Persist Security Info=True";
3       conn.Open();
4       SqlDataAdapter da = new SqlDataAdapter("select * from 表", conn);
5       SqlCommandBuilder thisBulder = new SqlCommandBuilder(da);
6       DataSet ds = new DataSet();
7       da.Fill(ds);
8       ds.WriteXml(@"C:\temp.xml");

 1 private void WriteXmlToFile(DataSet thisDataSet)
2  {
3     if (thisDataSet == null) { return; }
4     // Create a file name to write to.
 5     string filename = "myXmlDoc.xml";
6     // Create the FileStream to write with.
 7     System.IO.FileStream myFileStream = new System.IO.FileStream
8        (filename, System.IO.FileMode.Create);
9     // Create an XmlTextWriter with the fileStream.
10     System.Xml.XmlTextWriter myXmlWriter =
11        new System.Xml.XmlTextWriter(myFileStream, System.Text.Encoding.Unicode);
12     // Write to the file with the WriteXml method.
13     thisDataSet.WriteXml(myXmlWriter);
14     myXmlWriter.Close();
15  }