private void rules_btn_Click(object sender, EventArgs e)
{
if (rulesForm == null)
{
rulesForm = new RulesForm();
rulesForm.FormClosed += RulesForm_FormClosed;
}
this.Hide();
rulesForm.Show();
}
private void RulesForm_FormClosed(object sender, FormClosedEventArgs e)
{
rulesForm.FormClosed -= RulesForm_FormClosed;
rulesForm = null;
}