Showing AutoCAD field dialog box using ObjectARX

void addFieldWithDialog()

{

    AcGePoint3d pnt1;

     // pick start point

    if(acedGetPoint(NULL, L"\nPick Insertion point ",

                                        asDblArray(pnt1)) != RTNORM)

    {

        return;

    }

    AcDbDatabase *pDb =

      acdbHostApplicationServices()->workingDatabase();

    AcDbField *pField = NULL;

    Acad::ErrorStatus es;

    //show the dialog box..

    if(AcFdUiInvokeFieldDialog(pField, FALSE, pDb) == IDOK)

    {

        //open the model space for write

        AcDbObjectId modelId;

        modelId = acdbSymUtil()->blockModelSpaceId(pDb);

        AcDbBlockTableRecord *pBlockTableRecord;

        es = acdbOpenAcDbObject((AcDbObject*&)pBlockTableRecord,

                                        modelId, AcDb::kForWrite);

        //add a Mtext;

        AcDbMText *pMText = new AcDbMText();

        pMText->setLocation(pnt1);

        // Add to Db

        AcDbObjectId objectId;

        pBlockTableRecord->appendAcDbEntity(objectId, pMText);

        AcDbObjectId fieldId;

        //add a field

        es = pMText->setField(_T("TEXT"), pField, fieldId);

        es = pField->evaluate(AcDbField::kDemand, pDb); 

        pField->close();

        pMText->close();

        pBlockTableRecord->close();

    }

}