private void ReturnBtn_Click(object sender, EventArgs e)
{
this.Hide();
MainGUI f1 = new MainGUI();
f1.ShowDialog();
this.Close();
}
private void button2_Click(object sender, EventArgs e)
{
this.Hide();
MainGUI mainGUI = new MainGUI();
mainGUI.Closed += (s, args) => this.Close();
mainGUI.Show();
}
private void button3_Click(object sender, EventArgs e) // return button
{
this.Hide();
MainGUI f1 = new MainGUI();
f1.ShowDialog();
this.Close();
}