IList转DataSet(支持Nullable)

public static DataSet ConvertToDataSet<T>(IList<T> list)
        ...{
            if (list == null || list.Count <= 0)
                return null;

            DataSet ds = new DataSet();
            DataTable dt = new DataTable(typeof(T).Name);
            DataColumn column;
            DataRow row;

            System.Reflection.PropertyInfo[] myPropertyInfo =
                typeof(T).GetProperties(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance);

            foreach (T t in list)
            ...{
                if (t == null) continue;
                row = dt.NewRow();

                for (int i = 0, j = myPropertyInfo.Length; i < j; i++)
                ...{
                    System.Reflection.PropertyInfo pi = myPropertyInfo[i];
                    String name = pi.Name;
                    
                    if (dt.Columns[name] == null)
                    ...{
                        if (pi.PropertyType.UnderlyingSystemType.ToString() == "System.Nullable`1[System.Int32]")
                        ...{
                            column = new DataColumn(name,typeof(Int32));
                            dt.Columns.Add(column);
                            //row[name] = pi.GetValue(t, new object[] {i});//PropertyInfo.GetValue(object,object[])
                            if (pi.GetValue(t, null) != null)
                                row[name] = pi.GetValue(t, null);
                            else
                                row[name] = System.DBNull.Value;
                        }
                        else
                        ...{
                            column = new DataColumn(name, pi.PropertyType);
                            dt.Columns.Add(column);
                            row[name] = pi.GetValue(t, null);
                        }
                    }
                }
                dt.Rows.Add(row);
            }
            ds.Tables.Add(dt);
            return ds;
        }