A question about reading the block's xdata.

[ysx1993]

I use QCadCam software to create a DXF file about CAM, and this DXF file contains some cam-related data, some of the data is in the block entity, and then I use dxflib to read this DXF file, the addXDataString() interface is used to retrieve CAM data from block entity, but use libdxfrw to read DXF file, DRW_Block.extData.size () is 0, why?

[ysx1993]

This is dxf file:
CAM_2022_02_08.zip

[ysx1993]

libdxfrw codes:

#include <QCoreApplication>
#include <libdxfrw.h>
#include <QDebug>

class DxfFileReader : public DRW_Interface
{
public:
    void addHeader(const DRW_Header *data)
    {

    }
    void addLType(const DRW_LType &data)
    {
    }
    void addLayer(const DRW_Layer &data)
    {

    }
    void addDimStyle(const DRW_Dimstyle &data)
    {
    }
    void addVport(const DRW_Vport &data)
    {
    }
    void addTextStyle(const DRW_Textstyle &data)
    {
    }
    void addAppId(const DRW_AppId &data)
    {
    }
    void addBlock(const DRW_Block &data)
    {
        for (const std::shared_ptr<DRW_Variant> &extData : data.extData) {
            switch (extData->type()) {
            case DRW_Variant::STRING:
                qDebug() << extData->content.s->c_str();
                break;
            }
        }
    }
    void setBlock(const int handle)
    {

    }
    void endBlock()
    {

    }
    void addPoint(const DRW_Point &data)
    {
    }
    void addLine(const DRW_Line &data)
    {
        for (const std::shared_ptr<DRW_Variant> &extData : data.extData) {
            switch (extData->type()) {
            case DRW_Variant::STRING:
                qDebug() << extData->content.s->c_str();
                break;
            }
        }
    }
    void addRay(const DRW_Ray &data)
    {
    }
    void addXline(const DRW_Xline &data)
    {
    }
    void addArc(const DRW_Arc &data)
    {
    }
    void addCircle(const DRW_Circle &data)
    {
    }
    void addEllipse(const DRW_Ellipse &data)
    {
    }
    void addLWPolyline(const DRW_LWPolyline &data)
    {
    }
    void addPolyline(const DRW_Polyline &data)
    {
    }
    void addSpline(const DRW_Spline *data)
    {
    }
    void addKnot(const DRW_Entity &data)
    {
    }
    void addInsert(const DRW_Insert &data)
    {
    }
    void addTrace(const DRW_Trace &data)
    {
    }
    void add3dFace(const DRW_3Dface &data)
    {
    }
    void addSolid(const DRW_Solid &data)
    {
    }
    void addMText(const DRW_MText &data)
    {
    }
    void addText(const DRW_Text &data)
    {
    }
    void addDimAlign(const DRW_DimAligned *data)
    {
    }
    void addDimLinear(const DRW_DimLinear *data)
    {
    }
    void addDimRadial(const DRW_DimRadial *data)
    {
    }
    void addDimDiametric(const DRW_DimDiametric *data)
    {
    }
    void addDimAngular(const DRW_DimAngular *data)
    {
    }
    void addDimAngular3P(const DRW_DimAngular3p *data)
    {
    }
    void addDimOrdinate(const DRW_DimOrdinate *data)
    {
    }
    void addLeader(const DRW_Leader *data)
    {
    }
    void addHatch(const DRW_Hatch *data)
    {
    }
    void addViewport(const DRW_Viewport &data)
    {
    }
    void addImage(const DRW_Image *data)
    {
    }
    void linkImage(const DRW_ImageDef *data)
    {
    }
    void addComment(const char *comment)
    {
    }
    void addPlotSettings(const DRW_PlotSettings *data)
    {
    }
    void writeHeader(DRW_Header &data)
    {
    }
    void writeBlocks()
    {
    }
    void writeBlockRecords()
    {
    }
    void writeEntities()
    {
    }
    void writeLTypes()
    {
    }
    void writeLayers()
    {
    }
    void writeTextstyles()
    {
    }
    void writeVports()
    {
    }
    void writeDimstyles()
    {
    }
    void writeObjects()
    {
    }
    void writeAppId()
    {
    }
};

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    DxfFileReader reader;
    dxfRW dxfReader("C:/Users/ysx1993/Desktop/CAM_2022_02_08.dxf");
    dxfReader.read(&reader, true);

    return a.exec();
}

dxflib codes:

#include <QCoreApplication>
#include <dl_creationadapter.h>
#include <dl_dxf.h>
#include <QDebug>

class CreationAdapter : public DL_CreationAdapter {
public:
    void addBlock(const DL_BlockData &data)
    {
        qDebug() << data.name.c_str();
    }
    void addXDataString(int code, const std::string &value)
    {
        qDebug() << value.c_str();
    }
};

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    CreationAdapter adapter;
    DL_Dxf dxf;
    if (!dxf.in("C:/Users/ysx1993/Desktop/CAM_2022_02_08.dxf", &adapter))
        return 0;

    return a.exec();
}