'DataGridView3' does not exist in current context ,An object reference is required for the non-static field, method, or property Getting those 2 errors while reusing vb code in c#

private void dataGridView3_CellClick(object sender, DataGridViewCellEventArgs e)
       {

           invoice.dg1.Rows.Add(   DataGridView3.Item(0, e.RowIndex).Value,
                                   DataGridView3.Item(1, e.RowIndex).Value,
                                   DataGridView3.Item(2, e.RowIndex).Value,
                                   DataGridView3.Item(3, e.RowIndex).Value,
                                   DataGridView3.Item(4, e.RowIndex).Value
                                    );
       }