Get Total Quantity from Datagridview in C#.NET

Today , we will see "Get Total from Quantity Column in DataGridView in C#.Net"

Code
private double ADDCoulmnValue(int ColIdx, DataGridView dgv) { for (int idx = 0;idx <dgv.Rows.Count;idx++)
{ tot += Convert.ToDouble(dgv.Rows[idx].Cells[ColIdx].Value);
} }