private void btnDanhMucSua_Click(object sender, EventArgs e)
        {
            if (tlDanhMuc.FocusedNode == null) return;

            category cat = (category)tlDanhMuc.GetDataRecordByNode(tlDanhMuc.FocusedNode);
            FrmSuaDanhMuc frm = new FrmSuaDanhMuc();
            frm.Cat = cat;
            DialogResult r = frm.ShowDialog();
            if (r == DialogResult.OK)
            {
                XtraMessageBox.Show("Sửa danh mục thành công", this.Text, MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1);
                btnDanhMucLamMoi.PerformClick();
            }
        }
        private void btnDanhMucSua_Click(object sender, EventArgs e)
        {
            if (tlDanhMuc.FocusedNode == null)
            {
                return;
            }

            category      cat = (category)tlDanhMuc.GetDataRecordByNode(tlDanhMuc.FocusedNode);
            FrmSuaDanhMuc frm = new FrmSuaDanhMuc();

            frm.Cat = cat;
            DialogResult r = frm.ShowDialog();

            if (r == DialogResult.OK)
            {
                XtraMessageBox.Show("Sửa danh mục thành công", this.Text, MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1);
                btnDanhMucLamMoi.PerformClick();
            }
        }