private void lênLịchChiTiêuToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.Hide();
            FormKehoachchitieu lenlich = new FormKehoachchitieu();

            lenlich.Show();
        }
        private void lênSựKiệnToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.Hide();
            FormKehoachchitieu kehoachchitieu = new FormKehoachchitieu();

            kehoachchitieu.Show();
        }