transfer information from windows form to dataGridView

i want by select combobox and inter
transfer data to datagrid
Such stores that the customer will select multiple items
in fact i have multiple item but i cant send to datagrid

i have code,name,price,count

private void comboBox2_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Return)
listBox1.Items.Add(l1+ ")"+comboBox2.Text + " " + textBox4.Text + " " + textBox5.Text);
}
this code transfer data to listbox but i want transfer to datagridviwe:
l1:mycode,combobox1:name,texbox4:count,texbox5:price
i have multiple item but i cant send to datagrid

only i get data from table but i cant send to datagrid

private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
{


textBox5.Text = comboBox2.SelectedValue.ToString();
textBox5.Text = (int.Parse(textBox5.Text) * int.Parse(textBox4.Text)).ToString();

srch1(comboBox2.SelectedValue.ToString());
label10.Text = l1;
label11.Text = q1;
label12.Text = textBox5.Text;


}
void srch1(string Idddd)
{
foreach (information1 f1 in ist1)
{
if (f1.price_id == Idddd)
{
l1 = f1.price_id;
q1 = f1.price_type;
textBox5.Text = f1.price;
}


}
}