private void btnEditContact_Click(object sender, EventArgs e)
{
SecondForm secondForm = new SecondForm(this);
secondForm.EditContact(currentContact);
secondForm.Show();
listBox.Items.Remove(currentContact);
}
private void btnAddContact_Click(object sender, EventArgs e)
{
SecondForm secondForm = new SecondForm(this); //(this))
secondForm.Show();
}