C＃datagridview列出

Question

I am currently developing an point of sale system so i have a datagridview for the pay form and there are data loaded from the database that has the data of the products, but i need to calculate the total of the sum of the products but also i have a quantity column which i need. What do you suggest ? Should i convert the elements from the datagridview to list ?

Here is what i have tried:

 private void textBox1_TextChanged(object sender, EventArgs e)
    {
        MySqlConnection connection = Connection.prevzemiKonekcija();

        connection.Open();
        try {

            MySqlCommand command;
            MySqlDataAdapter adapter;
            DataTable tabela;


            string query = "SELECT  barcode,ProductName, SellPrice FROM artikli WHERE barcode  like '%" + txtBarajKod.Text + "%'";


            command = new MySqlCommand(query, connection);
            adapter = new MySqlDataAdapter(command);
            tabela = new DataTable();


            dataGridView1.DataSource = tabela;
            adapter.Fill(tabela);

            dataGridView1.Columns[1].HeaderText = "Шифра";
            dataGridView1.Columns[2].HeaderText = "Назив";
            dataGridView1.Columns[3].HeaderText = "Цена";


        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
        finally {
            connection.Close();
        }
    }

Answer 1

You could achieve this by looping on your rows and calculating the sum:

decimal total = 0;

foreach (var row in dataGridView1.Rows)
{
    // 1 is the index of your Quantity column
    var qty = Convert.ToInt32(row.Cells[1].Value);

    // 2 is the index of your Price column
    var price = Convert.ToDecimal(row.Cells[2].Value);

    total += qty * price;
}

Answer 2

You could add a column of Qty * Price. You only have to do this once.

DataColumn subTotalColumn = new DataColumn();
subTotalColumn.DataType = System.Type.GetType("System.Decimal");
subTotalColumn.ColumnName = "ItemTotal";
subTotalColumn.Expression = "Qty * Price";
((Data.DataTable)dataGridView1.DataSource).Columns.Add(subTotalColumn);

Then you can do a Compute:

decimal computedTotal = ((Data.DataTable)dataGridView1.DataSource).Compute("Sum(ItemTotal)");