private void списокГПToolStripMenuItem_Click(object sender, EventArgs e) { if (f15 == null) { f15 = new Form15(); f15.MdiParent = this; f15.FormClosed += new FormClosedEventHandler(f15_FormClosed); f15.Show(); } else { f15.Activate(); } }
void f15_FormClosed(object sender, FormClosedEventArgs e) { f15 = null; }