I have a dataGridView bound to a dataTable with columns like

Ticket_Num_From Ticket_Num_To Total_Tickets.

It is required that when Ticket_Num_To is filled by user Total_Tickets column get automatically calculated
(Ticket_Num_To - Ticket_Num_From + 1).

I have tried it on ColumnChanged event of dataTable but with limited success.

If somebody could help me on this pls.

Many thanks in advance.

int a, b;
private void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
    {

            b = (dataGridView1.CurrentRow.Index);
            if ((dataGridView1.Rows[b].Cells[0].Value) != null)
            {
                if (dataGridView1.CurrentCell.ColumnIndex==0)
                {
                        a=Convert.ToInt32(dataGridView1.Rows[b].Cells[0].Value);
                        b=convert.ToInt32(dataGridView1.Rows[b].Cells[1].Value);
            dataGridView1.Rows[b].Cells[2].Value=(a-b)+1;
                }
            }


    }