private void sinhViênToolStripMenuItem_Click(object sender, EventArgs e) { Khoa_Lop frm2 = new Khoa_Lop(); frm2.MdiParent = this; frm2.Show(); }
private void button4_Click(object sender, EventArgs e) { this.Close(); Khoa_Lop frm = new Khoa_Lop(); frm.Show(); }