static void gridRow2class( wxGrid* grid, int row, NETCLASSPTR nc )
{
#define MYCELL( col )   \
    ValueFromString( g_UserUnit, grid->GetCellValue( row, col ) )

    nc->SetClearance( MYCELL( GRID_CLEARANCE ) );
    nc->SetTrackWidth( MYCELL( GRID_TRACKSIZE ) );
    nc->SetViaDiameter( MYCELL( GRID_VIASIZE ) );
    nc->SetViaDrill( MYCELL( GRID_VIADRILL ) );
    nc->SetuViaDiameter( MYCELL( GRID_uVIASIZE ) );
    nc->SetuViaDrill( MYCELL( GRID_uVIADRILL ) );
}
    void ReadParam( wxConfigBase* aConfig ) const override
    {
        if( !m_Pt_param || !aConfig )
            return;

        wxString oldPath = aConfig->GetPath();

        m_Pt_param->Clear();

        for( int index = 0; ; ++index )
        {
            wxString    path = "";
            NETCLASSPTR netclass;
            wxString    netclassName;

            if( index == 0 )
                path = "Default";
            else
                path << index;

            aConfig->SetPath( oldPath );
            aConfig->SetPath( m_Ident );
            aConfig->SetPath( path );

            if( !aConfig->Read( NetclassNameKey, &netclassName ) )
                break;

            if( index == 0 )
                netclass = m_Pt_param->GetDefault();
            else
                netclass = std::make_shared<NETCLASS>( netclassName );

#define READ_MM( aKey, aDefault ) Millimeter2iu( aConfig->ReadDouble( aKey, aDefault ) )
            netclass->SetClearance( READ_MM( ClearanceKey, netclass->GetClearance() ) );
            netclass->SetTrackWidth( READ_MM( TrackWidthKey, netclass->GetTrackWidth() ) );
            netclass->SetViaDiameter( READ_MM( ViaDiameterKey, netclass->GetViaDiameter() ) );
            netclass->SetViaDrill( READ_MM( ViaDrillKey, netclass->GetViaDrill() ) );
            netclass->SetuViaDiameter( READ_MM( uViaDiameterKey, netclass->GetuViaDiameter() ) );
            netclass->SetuViaDrill( READ_MM( uViaDrillKey, netclass->GetuViaDrill() ) );
            netclass->SetDiffPairWidth( READ_MM( dPairWidthKey, netclass->GetDiffPairWidth() ) );
            netclass->SetDiffPairGap( READ_MM( dPairGapKey, netclass->GetDiffPairGap() ) );
            netclass->SetDiffPairViaGap( READ_MM( dPairViaGapKey, netclass->GetDiffPairViaGap() ) );

            if( index > 0 )
                m_Pt_param->Add( netclass );
        }

        aConfig->SetPath( oldPath );
    }