DataTable 與ToList 互轉

DataDable -> ToList<T>

public static List<T> ToList<T>(this DataTable dt)
        {
            var dataColumn = dt.Columns.Cast<DataColumn>().Select(c => c.ColumnName).ToList();

            var properties = typeof(T).GetProperties();
            string columnName = string.Empty;

            return dt.AsEnumerable().Select(row =>
            {
                var t = Activator.CreateInstance<T>();
                foreach (var p in properties)
                {
                    columnName = p.Name;
                    if (dataColumn.Contains(columnName))
                    {
                        if (!p.CanWrite)
                            continue;

                        object value = row[columnName];
                        Type type = p.PropertyType;

                        if (value != DBNull.Value)
                        {
                            p.SetValue(t, Convert.ChangeType(value, type), null);
                        }
                    }
                }
                return t;
            }).ToList();
        }

ToList<T> ->  DataDable 

public static DataTable ToDataTable<T>(this List<T> items)
        {
            DataTable dataTable = new DataTable();

            PropertyInfo[] Props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);
            foreach (PropertyInfo prop in Props)
            {
                dataTable.Columns.Add(prop.Name,prop.PropertyType);
            }

            foreach (T obj in items)
            {
                var values = new object[Props.Length];
                for (int i = 0; i < Props.Length; i++)
                {
                    values[i] = Props[i].GetValue(obj, null);
                }
                dataTable.Rows.Add(values);
            }

            return dataTable;
        }