循环访问块表记录

下面的示例演示如何循环访问块表记录中的元素并打印出元素。

该函数打开块表进行读取，然后打开用户提供的块名称。新的迭代器逐步执行块表记录。如果记录包含实体，迭代器将打印有关该实体的消息。printAll()

void
printAll()
{
    int rc;
    char blkName[50];
    rc = acedGetString(Adesk::kTrue,
        "Enter Block Name <CR for current space>: ",
        blkName);
    if (rc != RTNORM)
        return;
    if (blkName[0] == '\0') {
        if (acdbHostApplicationServices()->workingDatabase()
            ->tilemode() == Adesk::kFalse) {
            struct resbuf rb;
            acedGetVar("cvport", &rb);
            if (rb.resval.rint == 1) {
                strcpy(blkName, ACDB_PAPER_SPACE);
            } else {
                strcpy(blkName, ACDB_MODEL_SPACE);
            }
        } else {
            strcpy(blkName, ACDB_MODEL_SPACE);
        }
    }
    AcDbBlockTable *pBlockTable;
    acdbHostApplicationServices()->workingDatabase()
        ->getSymbolTable(pBlockTable, AcDb::kForRead);
    AcDbBlockTableRecord *pBlockTableRecord;
    pBlockTable->getAt(blkName, pBlockTableRecord,
        AcDb::kForRead);
    pBlockTable->close();
    AcDbBlockTableRecordIterator *pBlockIterator;
    pBlockTableRecord->newIterator(pBlockIterator);
    for (; !pBlockIterator->done();
        pBlockIterator->step())
    {
        AcDbEntity *pEntity;
        pBlockIterator->getEntity(pEntity, AcDb::kForRead);
        AcDbHandle objHandle;
        pEntity->getAcDbHandle(objHandle);
        char handleStr[20];
        objHandle.getIntoAsciiBuffer(handleStr);
        const char *pCname = pEntity->isA()->name();
        acutPrintf("Object Id %lx, handle %s, class %s.\n",
            pEntity->objectId(), handleStr, pCname);
        pEntity->close();
    }
    delete pBlockIterator;
    pBlockTableRecord->close();
    acutPrintf("\n");
}