private void dgv_CellEndEdit(object sender, DataGridViewCellEventArgs e)
{
int MaxRows = dgv.Rows.Count;
for (int i = 0; i < MaxRows-1; i++)
{
SqlDataAdapter da = new SqlDataAdapter("SELECT CAST(originalPrice * " + (1.00 + (float.Parse(txtMarkUp.Text) / 100.00)).ToString() + " * " + (1.00 + (float.Parse(dgv.Rows[i].Cells[4].Value.ToString()) / 100.00)).ToString() + " AS decimal (8,2)) AS sellingPrice FROM Warehouse WHERE barcode = '" + Convert.ToString(dgv.Rows[i].Cells[2].Value) + "'", conn);
DataTable dt = new DataTable();
da.Fill(dt);
DataGridViewComboBoxColumn sellingPrice = dgv.Columns["sellingPrice"] as DataGridViewComboBoxColumn;
sellingPrice.DataSource = dt;
sellingPrice.ValueMember = …
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