DatagridView How to have a different row count per column?

Question

So I was trying to display my data in specific format in a datagridview. So my format goes like this:

A B C

1 1 1

2 2 x

3 x x

t

Answer 1

To expand on jdweng's answer, if for some reason you truly want:

[T]he x means no cell.

Then you can handle the DataGridView.CellPainting event to effectively hide the empty cell. Mind you, it will start to look odd when null cells are intermingled amidst valued cells - and not just at the row ends.

// ...
dt.Rows.Add(new object[] { 3, null, null });

this.dataGridView1.DataSource = dt;
this.dataGridView1.CellPainting += DataGridView1_CellPainting;

---

private void DataGridView1_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
    if (e.RowIndex >= 0 && e.ColumnIndex >= 0)
    {
        DataGridViewCell cell = this.dataGridView1[e.ColumnIndex, e.RowIndex];

        if (cell.Value == null || cell.Value is DBNull)
        {
            using (SolidBrush brush = new SolidBrush(this.dataGridView1.BackgroundColor))
            {
                e.Graphics.FillRectangle(brush, e.CellBounds);
            }

            e.Handled = true;
        }
    }
}

Answer 2

Try following

            DataTable dt = new DataTable("MyDataTable");

            dt.Columns.Add("A", typeof(int));
            dt.Columns.Add("B", typeof(int));
            dt.Columns.Add("C", typeof(int));

            dt.Columns["A"].AllowDBNull = true;
            dt.Columns["B"].AllowDBNull = true;
            dt.Columns["C"].AllowDBNull = true;

            dt.Rows.Add(new object[] { 1,2,3});
            dt.Rows.Add(new object[] { 2, 2, });
            dt.Rows.Add(new object[] { 3 });

            datagridview1.DataSource = dt;