private void btnThemNam_Click(object sender, EventArgs e) { var frm = new frmNamHoc(); if (Application.OpenForms[frm.Name] == null) { frm.Show(); } else { Application.OpenForms[frm.Name].Focus(); } }
private void btnNamHoc_ItemClick(object sender, ItemClickEventArgs e) { Form frm = this.KiemTraTonTai(typeof(frmNamHoc)); if (frm != null) { frm.Activate(); } else { frmNamHoc f = new frmNamHoc { MdiParent = this }; f.Show(); } }