dt.TableName = "ProText";
dt.WriteXml(Application.StartupPath +@"\1.xml");//序列化成功

下面反序列化不成功，是不是思路错了?
private string filePath =Application.StartupPath +@"\1.xml";        
StringReader strReader = new StringReader(filePath);
XmlReader xmlReader = XmlReader.Create(strReader);
XmlSerializer serializer = new XmlSerializer(typeof(DataTable));
DataTable dt = serializer.Deserialize(xmlReader) as DataTable;
dgvColumn.DataSource = dt;//数据为空。