C# 我可以使列的值延迟数据绑定吗？

我有一个包含几列的表，我想添加一列，但不首先为其提供值，因为它是一个有点复杂的对象，可能不会在每次使用该表时都有用

因此，我当前的代码如下所示：

            var com = new SqlConnection(functions.ConnectionString).CreateCommand();
            com.CommandText = @"
SELECT
    S.id
    , S.Name
    , S.MemberID
FROM dbo.SubSets AS S
WHERE S.SubsetType = 0
AND S.MemberId > 1
";
            this.tblSubsets = new DataTable();

            new SqlDataAdapter(com).Fill(this.tblSubsets);

            this.tblSubsets.Columns.Add(new DataColumn()
            {
                AllowDBNull = true
                , ColumnName = "Member"
                , DataType = typeof(object) // ?
                , DefaultValue = DBNull.Value // late binding mechanism?
            });

如何使该列成员在被用于DoSomethingwithtable.Rows[x][Member]之前保持为空？

我想您不能

我最终存储了一个Func，并在向表中添加行时自动设置该字段。 此外，闭包中的字典还可以实现性能目标

            this.tblSubsets = new DataTable();

            this.tblSubsets.Columns.AddRange(new DataColumn[] {
                new DataColumn()
                {
                    AllowDBNull = false
                    , ColumnName = "Member"
                    , DataType = typeof(Func<Member>)
                }
            });

            var members = new Dictionary<int, Member>();
            this.tblSubsets.RowChanged += new DataRowChangeEventHandler((object sender, DataRowChangeEventArgs e) =>
            {
                if (e.Action != DataRowAction.Add)
                {
                    return;
                }

                e.Row["Member"] = new Func<Member>(() =>
                {
                    Member returnValue;
                    var mid = Convert.ToInt32(e.Row["MemberID"]);

                    if (!members.TryGetValue(mid, out returnValue))
                    {
                        members.Add(mid, (returnValue = new Member(mid)));
                    }

                    return returnValue;
                });
            });


            var com = new SqlConnection(functions.ConnectionString).CreateCommand();
            com.CommandText = @"
SELECT
    S.id
    , S.Name
    , S.MemberID
FROM dbo.SubSets AS S
WHERE S.SubsetType = 0
";
            new SqlDataAdapter(com).Fill(this.tblSubsets);