public static class DataTableEntityInteroperate{/// <summary>/// List<T> to DataTable/// </summary>/// <typeparam name="T">Entity</typeparam>/// <param name="entities">Entities</param>/// <returns>DataTable</returns>internal static DataTable ToDataTable<T>(this List<T> entities) where T : class,new(){//IsNull returnif (null == entities || entities.Count == 0)return null;//Initial ColumnsDataTable dt = new DataTable();PropertyInfo[] pArray = typeof(T).GetProperties();try{Array.ForEach<PropertyInfo>(pArray, p =>{dt.Columns.Add(p.Name);});entities.ForEach(t =>{                   //Initial Rows                DataRow dr=dt.NewRow();int i = 0;Array.ForEach<PropertyInfo>(pArray, p =>{if (dt.Columns.Contains(p.Name))dr[i] = p.GetValue(t); //Assigned to each column
                });i++;                                dt.Rows.Add(dr);//备忘，测试不仔细。});return dt;}catch (Exception){throw;}}/// <summary>/// DataTable to Entities/// </summary>/// <typeparam name="T">Entity</typeparam>/// <param name="dt">DataTable</param>/// <returns>List<T</returns>internal static List<T> ToEntities<T>(this DataTable dt)/*必须来在于数据库来自于文件可能存在问题*/ where T : class,new(){//IsNullableif (null == dt || dt.Rows.Count == 0)return null;//Initial EntitiesList<T> entities = new List<T>();try{foreach (DataRow row in dt.Rows){PropertyInfo[] pArray = typeof(T).GetProperties();T entity = new T();Array.ForEach<PropertyInfo>(pArray, p =>{                     if(row[p.Name]!=DBNull.Value)p.SetValue(entity, row[p.Name], null);});entities.Add(entity);}return entities;}catch (Exception){throw;}}
}

public class XmlHelper
{/// <summary> /// 将XML转换为DATATABLE /// </summary> /// <param name="FileURL"></param> /// <returns></returns> public static DataTable XmlAnalysisArray(string filepath){try{DataSet ds = new DataSet();ds.ReadXml(filepath);return ds.Tables[0];}catch (Exception ex){throw ex;}}/// <summary> /// 将DATASET 转换为 XML/// </summary> /// <param name="FileURL"></param> /// <returns></returns> public static void DatasetConversionXML(DataSet ds, string FileURL){try{ds.WriteXml(FileURL);}catch (Exception ex){throw ex;}}/// <summary>/// Xml序列化/// </summary>/// <typeparam name="T">对象的类型</typeparam>/// <param name="t">序列化对象实例</param>/// <param name="filePath">文件路径</param>public static void XmlSerializer<T>(List<T> t, string filePath){XmlSerializer xmlSerializer = new XmlSerializer(typeof(List<T>));StreamWriter writer = new StreamWriter(filePath);//将s对象写入到指定的IO流文件中try{xmlSerializer.Serialize(writer, t);}catch (Exception){//errr message
        }finally{writer.Close();}}/// <summary>/// Xml反序列化/// </summary>/// <typeparam name="T">对象类型</typeparam>/// <param name="t">对象实例</param>public static List<T> XmlDeserialize<T>(List<T> t, string filePath)  //必须是经过同样的过程反序列化好的文件
    {XmlSerializer mySerializer = new XmlSerializer(typeof(List<T>));FileStream myFileStream = null;if (File.Exists(filePath))  //检查文件是否存在
        {try{myFileStream = new FileStream(filePath, FileMode.Open);t = (List<T>)mySerializer.Deserialize(myFileStream);}catch (FileNotFoundException){//File not Found
            }catch (Exception){//the other error message
            }finally{myFileStream.Close();}}return t;}}

 var dt = XmlHelper.XmlAnalysisArray(Server.MapPath(@"XML\Students"));var list= dt.ToEntities<Student>();