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C++ OGRFeature::SetFieldNull方法代码示例

本文整理汇总了C++中OGRFeature::SetFieldNull方法的典型用法代码示例。如果您正苦于以下问题：C++ OGRFeature::SetFieldNull方法的具体用法？C++ OGRFeature::SetFieldNull怎么用？C++ OGRFeature::SetFieldNull使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类OGRFeature的用法示例。


在下文中一共展示了OGRFeature::SetFieldNull方法的4个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: if

OGRFeature *OGRDB2Layer::GetNextRawFeature()

{

    if( GetStatement() == nullptr )
        return nullptr;

    /* -------------------------------------------------------------------- */
    /*      If we are marked to restart then do so, and fetch a record.     */
    /* -------------------------------------------------------------------- */
    if( !m_poStmt->Fetch() )  // fail is normal for final fetch
    {
//      CPLDebug("OGR_DB2Layer::GetNextRawFeature","Fetch failed");
        delete m_poStmt;
        m_poStmt = nullptr;
        return nullptr;
    }
//      CPLDebug("OGR_DB2Layer::GetNextRawFeature","Create feature");
    /* -------------------------------------------------------------------- */
    /*      Create a feature from the current result.                       */
    /* -------------------------------------------------------------------- */
    int         iField;
    OGRFeature *poFeature = new OGRFeature( poFeatureDefn );
    if( pszFIDColumn != nullptr && m_poStmt->GetColId(pszFIDColumn) > -1 )
        poFeature->SetFID(
            atoi(m_poStmt->GetColData(m_poStmt->GetColId(pszFIDColumn))) );
    else
        poFeature->SetFID( iNextShapeId );

    iNextShapeId++;
    m_nFeaturesRead++;

    /* -------------------------------------------------------------------- */
    /*      Set the fields.                                                 */
    /* -------------------------------------------------------------------- */

    for( iField = 0; iField < poFeatureDefn->GetFieldCount(); iField++ )
    {
        if ( poFeatureDefn->GetFieldDefn(iField)->IsIgnored() )
            continue;

        int iSrcField = panFieldOrdinals[iField];
        const char *pszValue = m_poStmt->GetColData( iSrcField );

        if( pszValue == nullptr )
            poFeature->SetFieldNull( iField );
        else if( poFeature->GetFieldDefnRef(iField)->GetType() == OFTBinary )
            poFeature->SetField( iField,
                                 m_poStmt->GetColDataLength(iSrcField),
                                 (GByte *) pszValue );
        else
            poFeature->SetField( iField, pszValue );
    }

    /* -------------------------------------------------------------------- */
    /*      Try to extract a geometry.                                      */
    /* -------------------------------------------------------------------- */

    if( pszGeomColumn != nullptr && !poFeatureDefn->IsGeometryIgnored())
    {
        iField = m_poStmt->GetColId( pszGeomColumn );
        const char *pszGeomText = m_poStmt->GetColData( iField );
        OGRGeometry *poGeom = nullptr;
        OGRErr eErr = OGRERR_NONE;
        if( pszGeomText != nullptr )
        {
            eErr = OGRGeometryFactory::createFromWkt(pszGeomText,
                    nullptr, &poGeom);
        }

        if ( eErr != OGRERR_NONE )
        {
            const char *pszMessage;

            switch ( eErr )
            {
            case OGRERR_NOT_ENOUGH_DATA:
                pszMessage = "Not enough data to deserialize";
                break;
            case OGRERR_UNSUPPORTED_GEOMETRY_TYPE:
                pszMessage = "Unsupported geometry type";
                break;
            case OGRERR_CORRUPT_DATA:
                pszMessage = "Corrupt data";
                break;
            default:
                pszMessage = "Unrecognized error";
            }
            CPLError(CE_Failure, CPLE_AppDefined,
                     "GetNextRawFeature(): %s", pszMessage);
        }

        if( poGeom != nullptr )
        {
            if ( GetSpatialRef() )
                poGeom->assignSpatialReference( poSRS );

            poFeature->SetGeometryDirectly( poGeom );
        }
    }
//.........这里部分代码省略.........
开发者ID:OSGeo，项目名称:gdal，代码行数:101，代码来源:ogrdb2layer.cpp

示例2: if

OGRFeature *OGRMSSQLSpatialLayer::GetNextRawFeature()

{
    if( GetStatement() == NULL )
        return NULL;

/* -------------------------------------------------------------------- */
/*      If we are marked to restart then do so, and fetch a record.     */
/* -------------------------------------------------------------------- */
    if( !poStmt->Fetch() )
    {
        delete poStmt;
        poStmt = NULL;
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Create a feature from the current result.                       */
/* -------------------------------------------------------------------- */
    OGRFeature *poFeature = new OGRFeature( poFeatureDefn );

    const char* pszFID;
    if( pszFIDColumn != NULL && poStmt->GetColId(pszFIDColumn) > -1 &&
        (pszFID = poStmt->GetColData(poStmt->GetColId(pszFIDColumn))) != NULL )
        poFeature->SetFID( CPLAtoGIntBig(pszFID) );
    else
        poFeature->SetFID( iNextShapeId );

    iNextShapeId++;
    m_nFeaturesRead++;

/* -------------------------------------------------------------------- */
/*      Set the fields.                                                 */
/* -------------------------------------------------------------------- */
    for( int iField = 0; iField < poFeatureDefn->GetFieldCount(); iField++ )
    {
        if ( poFeatureDefn->GetFieldDefn(iField)->IsIgnored() )
            continue;

        int iSrcField = panFieldOrdinals[iField];
        const char *pszValue = poStmt->GetColData( iSrcField );

        if( pszValue == NULL )
            poFeature->SetFieldNull( iField );
        else if( poFeature->GetFieldDefnRef(iField)->GetType() == OFTBinary )
            poFeature->SetField( iField,
                                 poStmt->GetColDataLength(iSrcField),
                                 (GByte *) pszValue );
        else
            poFeature->SetField( iField, pszValue );
    }

/* -------------------------------------------------------------------- */
/*      Try to extract a geometry.                                      */
/* -------------------------------------------------------------------- */
    if( pszGeomColumn != NULL && !poFeatureDefn->IsGeometryIgnored())
    {
        int iField = poStmt->GetColId( pszGeomColumn );
        const char *pszGeomText = poStmt->GetColData( iField );
        OGRGeometry *poGeom = NULL;
        OGRErr eErr = OGRERR_NONE;

        if( pszGeomText != NULL )
        {
            int nLength = poStmt->GetColDataLength( iField );

            if ( nGeomColumnType == MSSQLCOLTYPE_GEOMETRY ||
                 nGeomColumnType == MSSQLCOLTYPE_GEOGRAPHY ||
                 nGeomColumnType == MSSQLCOLTYPE_BINARY)
            {
                switch ( poDS->GetGeometryFormat() )
                {
                case MSSQLGEOMETRY_NATIVE:
                    {
                        OGRMSSQLGeometryParser oParser( nGeomColumnType );
                        eErr = oParser.ParseSqlGeometry(
                            (unsigned char *) pszGeomText, nLength, &poGeom );
                        nSRSId = oParser.GetSRSId();
                    }
                    break;
                case MSSQLGEOMETRY_WKB:
                case MSSQLGEOMETRY_WKBZM:
                    eErr = OGRGeometryFactory::createFromWkb((unsigned char *) pszGeomText,
                                                      NULL, &poGeom, nLength);
                    break;
                case MSSQLGEOMETRY_WKT:
                    eErr = OGRGeometryFactory::createFromWkt((char **) &pszGeomText,
                                                      NULL, &poGeom);
                    break;
                }
            }
            else if (nGeomColumnType == MSSQLCOLTYPE_TEXT)
            {
                eErr = OGRGeometryFactory::createFromWkt((char **) &pszGeomText,
                                                      NULL, &poGeom);
            }
        }

        if ( eErr != OGRERR_NONE )
        {
//.........这里部分代码省略.........
开发者ID:Mavrx-inc，项目名称:gdal，代码行数:101，代码来源:ogrmssqlspatiallayer.cpp

示例3: OGRFeature

OGRFeature *OGRMySQLLayer::RecordToFeature( char **papszRow,
                                            unsigned long *panLengths )

{
    mysql_field_seek( hResultSet, 0 );

/* -------------------------------------------------------------------- */
/*      Create a feature from the current result.                       */
/* -------------------------------------------------------------------- */
    OGRFeature *poFeature = new OGRFeature( poFeatureDefn );

    poFeature->SetFID( iNextShapeId );
    m_nFeaturesRead++;

/* ==================================================================== */
/*      Transfer all result fields we can.                              */
/* ==================================================================== */
    for( int iField = 0;
         iField < (int) mysql_num_fields(hResultSet);
         iField++ )
    {
        MYSQL_FIELD *psMSField = mysql_fetch_field(hResultSet);

/* -------------------------------------------------------------------- */
/*      Handle FID.                                                     */
/* -------------------------------------------------------------------- */
        if( bHasFid && EQUAL(psMSField->name,pszFIDColumn) )
        {
            if( papszRow[iField] == NULL )
            {
                CPLError( CE_Failure, CPLE_AppDefined,
                          "NULL primary key in RecordToFeature()" );
                return NULL;
            }

            poFeature->SetFID( CPLAtoGIntBig(papszRow[iField]) );
        }

        if( papszRow[iField] == NULL )
        {
            const int iOGRField = poFeatureDefn->GetFieldIndex(psMSField->name);
            if( iOGRField >= 0 )
                poFeature->SetFieldNull( iOGRField );

            continue;
        }

/* -------------------------------------------------------------------- */
/*      Handle MySQL geometry                                           */
/* -------------------------------------------------------------------- */
        if( pszGeomColumn && EQUAL(psMSField->name,pszGeomColumn))
        {
            OGRGeometry *poGeometry = NULL;

            // Geometry columns will have the first 4 bytes contain the SRID.
            OGRGeometryFactory::createFromWkb(
                ((GByte *)papszRow[iField]) + 4,
                NULL,
                &poGeometry,
                static_cast<int>(panLengths[iField] - 4) );

            if( poGeometry != NULL )
            {
                poGeometry->assignSpatialReference( GetSpatialRef() );
                poFeature->SetGeometryDirectly( poGeometry );
            }
            continue;
        }

/* -------------------------------------------------------------------- */
/*      Transfer regular data fields.                                   */
/* -------------------------------------------------------------------- */
        const int iOGRField = poFeatureDefn->GetFieldIndex(psMSField->name);
        if( iOGRField < 0 )
            continue;

        OGRFieldDefn *psFieldDefn = poFeatureDefn->GetFieldDefn( iOGRField );

        if( psFieldDefn->GetType() == OFTBinary )
        {
            poFeature->SetField( iOGRField, static_cast<int>(panLengths[iField]),
                                 (GByte *) papszRow[iField] );
        }
        else
        {
            poFeature->SetField( iOGRField, papszRow[iField] );
        }
    }

    return poFeature;
}
开发者ID:Mavrx-inc，项目名称:gdal，代码行数:91，代码来源:ogrmysqllayer.cpp

示例4: if

OGRFeature *OGRWalkLayer::GetNextRawFeature()

{
    if( GetStatement() == nullptr )
        return nullptr;

/* -------------------------------------------------------------------- */
/*      If we are marked to restart then do so, and fetch a record.     */
/* -------------------------------------------------------------------- */
    if( !poStmt->Fetch() )
    {
        delete poStmt;
        poStmt = nullptr;
        return nullptr;
    }

/* -------------------------------------------------------------------- */
/*      Create a feature from the current result.                       */
/* -------------------------------------------------------------------- */
    OGRFeature *poFeature = new OGRFeature( poFeatureDefn );

    if( pszFIDColumn != nullptr && poStmt->GetColId(pszFIDColumn) > -1 )
        poFeature->SetFID(
            atoi(poStmt->GetColData(poStmt->GetColId(pszFIDColumn))) );
    else
        poFeature->SetFID( iNextShapeId );

    iNextShapeId++;
    m_nFeaturesRead++;

/* -------------------------------------------------------------------- */
/*      Set the fields.                                                 */
/* -------------------------------------------------------------------- */
    for( int iField = 0; iField < poFeatureDefn->GetFieldCount(); iField++ )
    {
        int iSrcField = panFieldOrdinals[iField]-1;
        const char *pszValue = poStmt->GetColData( iSrcField );

        if( pszValue == nullptr )
            poFeature->SetFieldNull( iField );
        else if( poFeature->GetFieldDefnRef(iField)->GetType() == OFTBinary )
            poFeature->SetField( iField,
                                 poStmt->GetColDataLength(iSrcField),
                                 (GByte *) pszValue );
        else
            poFeature->SetField( iField, pszValue );
    }

/* -------------------------------------------------------------------- */
/*      Try to extract a geometry.                                      */
/* -------------------------------------------------------------------- */
    if( pszGeomColumn != nullptr )
    {
        int iField = poStmt->GetColId( pszGeomColumn );
        const char *pszGeomBin = poStmt->GetColData( iField );
        int nGeomLength = poStmt->GetColDataLength( iField );
        OGRGeometry *poGeom = nullptr;
        OGRErr eErr = OGRERR_NONE;

        if( pszGeomBin != nullptr && bGeomColumnWKB )
        {
            WKBGeometry *WalkGeom = (WKBGeometry *)CPLMalloc(sizeof(WKBGeometry));
            if( Binary2WkbGeom((unsigned char *)pszGeomBin, WalkGeom, nGeomLength)
                != OGRERR_NONE )
            {
                CPLFree(WalkGeom);
                return nullptr;
            }
            eErr = TranslateWalkGeom(&poGeom, WalkGeom);

            DeleteWKBGeometry(*WalkGeom);
            CPLFree(WalkGeom);
        }

        if ( eErr != OGRERR_NONE )
        {
            const char *pszMessage = nullptr;

            switch ( eErr )
            {
                case OGRERR_NOT_ENOUGH_DATA:
                    pszMessage = "Not enough data to deserialize";
                    break;
                case OGRERR_UNSUPPORTED_GEOMETRY_TYPE:
                    pszMessage = "Unsupported geometry type";
                    break;
                case OGRERR_CORRUPT_DATA:
                    pszMessage = "Corrupt data";
                    break;
                default:
                    pszMessage = "Unrecognized error";
            }
            CPLError(CE_Failure, CPLE_AppDefined,
                     "GetNextRawFeature(): %s", pszMessage);
        }

        if( poGeom != nullptr && eErr == OGRERR_NONE )
        {
            poGeom->assignSpatialReference( poSRS );
            poFeature->SetGeometryDirectly( poGeom );
//.........这里部分代码省略.........
开发者ID:koordinates，项目名称:gdal，代码行数:101，代码来源:ogrwalklayer.cpp


注：本文中的OGRFeature::SetFieldNull方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台，相关代码片段筛选自各路编程大神贡献的开源项目，源码版权归原作者所有，传播和使用请参考对应项目的License；未经允许，请勿转载。