Your second form needs a reference to the first one:
Form37:
Edit the Form37
keydown event
private void Form37_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
Form38 f = new Form38();
f.caller_form = this;
this.Hide();
f.Show();
}
}
Form38:
Add a new variable to your Form38
class's root:
public partial class Form38 : Form
{
Form37 caller_form;
Edit the Form38
's dataGridView1
's keydown event
private void dataGridView1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
Form37 f = caller_form;
f.a = 1;
f.v = dataGridView1.SelectedCells[0].Value.ToString();
f.Show();
this.Close();
}
}