[C#.NET] مناداه method موجودة في ال user control من ال main form

PHP كود :
public void ShowGV()
        {
            try
            {
                //Filter = 0;
                _con.connection();
                if (_con.con.State == ConnectionState.Closed)
                {
                    _con.con.Open();
                }

                query_1 = "select * from inv_view";

                ds.Clear();
                dt.Rows.Clear();

                DataAdapter = new OleDbDataAdapter(query_1, _con.con);
                DataAdapter.Fill(ds, Filter, pagesize, "inv_view");
                DataAdapter.Fill(dt);

                R_count = dt.Rows.Count;
                _con.con.Close();

                GV.DataSource = ds.Tables[0];
                GV.Refresh();

                //GV.Columns.Insert(0,btn);
                GV.Columns[0].Visible = false;
                GV.Columns[1].Visible = false;
                GV.Columns[2].HeaderText = "اسم الزبون";
                GV.Columns[3].HeaderText = "رقم الهاتف";
                GV.Columns[4].HeaderText = "قيمة الفاتورة";
                GV.Columns[5].HeaderText = "القيمة المدفوعة";
                GV.Columns[6].HeaderText = "القيمة المتبقية";
                GV.Columns[7].HeaderText = "التاريخ";
                GV.Columns[8].HeaderText = "الملاحظات";
                GV.Columns[9].Visible = false;
                GV.Columns[10].HeaderText = "";

                GV.Columns[8].AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill;
                GV.Columns[4].DefaultCellStyle.Format = "C0";
                GV.Columns[5].DefaultCellStyle.Format = "C0";
                GV.Columns[6].DefaultCellStyle.Format = "C0";

                // Paging
                pagecount = Convert.ToDouble(R_count) / Convert.ToDouble(pagesize);
                TSCom.Items.Clear();

                for (int I = 1; I <= Math.Ceiling(pagecount); I++)
                {
                    TSCom.Items.Add(I.ToString());
                }

                toolStripLabel2.Text = "{" + Math.Ceiling(pagecount) + "} من";
                if (R_count > 0)
                {
                    TSCom.SelectedIndex = 0;
                }

                get_columns_sum();
            }
            catch (Exception ex)
            {
                MessageBox.Show("Error : " + ex);
            }
        }