private void créerUneLigueToolStripMenuItem1_Click(object sender, EventArgs e) { if (f1 == null) { f1 = new AddLigue(); f1.MdiParent = this; f1.FormClosed += F1_FormClosed; f1.Show(); Form childForm = new Form(); } else { f1.Activate(); } }
private void F1_FormClosed(object sender, FormClosedEventArgs e) { f1 = null; }