private void lớpToolStripMenuItem_Click(object sender, EventArgs e) { frmLop_Khoa frm = new frmLop_Khoa(); frm.MdiParent = this; frm.Show(); }
private void btnThoat_Click(object sender, EventArgs e) { this.Close(); frmLop_Khoa frm = new frmLop_Khoa(); frm.Show(); }