文件读取

1.序列化读写

/***单个类的写入***/CStudentDTO dtoA(1,_T("nameA"),11);CStudentDTO dtoB(2,_T("nameB"),22);CFile file;file.Open(_T("c:\\data.data"),CFile::modeCreate|CFile::modeWrite);CArchive ar(&file,CArchive::store);ar.WriteObject(&dtoA);ar.Flush();file.Close();file.Open(_T("c:\\data.data"),CFile::modeRead);            CArchive br(&file,CArchive::load);            CObList *pDtoList = (CObList *)br.ReadObject(CObject::GetThisClass());file.Close();

/***list<类>的写入***/CStudentDTO dtoA(1,_T("nameA"),11);CStudentDTO dtoB(2,_T("nameB"),22);CFile file;CObList list;list.AddTail(&dtoA);//这里写入的对象dtoA对应的类CStudentDTO必须是派生于CObject的类list.AddTail(&dtoB);file.Open(_T("c:\\data.data"),CFile::modeCreate|CFile::modeWrite);CArchive ar(&file,CArchive::store);ar.WriteObject(&list);ar.Flush();file.Close();file.Open(_T("c:\\data.data"),CFile::modeRead);CArchive br(&file,CArchive::load);CObList *pDtoList = (CObList *)br.ReadObject(CObList::GetThisClass());file.Close();POSITION pos = pDtoList->GetHeadPosition();while(pos!=NULL){CStudentDTO * stute = (CStudentDTO*)pDtoList->GetAt(pos);wstring d = stute->GetName();string tt(d.begin(),d.end());cout<<tt<<endl;pDtoList->GetNext(pos);}

2. ifstream/ofstream

void CFileDAO::Save(CMyList<CStudentDTO> &list){    ofstream out;    out.open("sort.txt");    //out.open("D:\\ok.data",ios::binary);      CStudentDTO *p;    list.GetHead(p);    for(int i = 0;i<list.fact_len;i++)          out<<p[i].GetID()<<"\t"<<p[i].GetName()<<"\t"<<p[i].GetChineseScore()<<"\t"          <<p[i].GetEnglishScore()<<'\n';      out.close(); }

void CFileDAO::Read(CMyList<CStudentDTO> &list){    ifstream in;    in.open("sort.txt");      //in.open("D:\\ok.data",ios::binary);    int id;    char name[20];    float chineseScore, englishScore;    if(in)    {        while(!in.eof())          {              in>>id>>name>>chineseScore>>englishScore;               CStudentDTO dto(id,name,chineseScore,englishScore);            mylist.push_back(dto);        }    }    in.close();  }

或者

void CFileDAO::Save(CMyList<CStudentDTO> &list){    ofstream file;    file.open("D:\\ok.data",ios::binary);    file<<mylist.size();    list<CStudentDTO>::iterator q;    for(q = mylist.begin();q!=mylist.end();p++)      {        CStudentDTO dto = *q;        file.write((char *)&dto,sizeof(CStudentDTO));    }    file.close(); }

void CFileDAO::Read(CMyList<CStudentDTO> &list){    ifstream file;    file.open("D:\\ok.data",ios::binary);    list<CStudentDTO>::iterator p;    int fact_num;    file>>fact_num;    for(int i = 0;i<fact_num;i++)      {        CStudentDTO dto;        file.read((char *)&dto,sizeof(CStudentDTO));        mylist.push_back(dto);    }    file.close(); }

3.数据库sqlite3中数据的读写

void MyDataBaseDAO::Save(list<CStudentDTO> &mylist){       try{        CppSQLite3DB db;        cout << "SQLite Version: " << db.SQLiteVersion() << endl;        TCHAR path[255] = {0};        GetModuleFileName(NULL,path,255);        (_tcsrchr(path,'\\'))[1]='\0';        string sd = path;        sd = sd + _T("test.db");        string ssss(sd.begin(),sd.end());        cout<<"SQLiteVersion:"<<db.SQLiteVersion()<<endl;        char *pppp = (char*)sd.c_str();        db.open(ssss.c_str());        //db.open("C:\\Users\\drilistbox\\Desktop\\test.db");        string cmd;        int nRows;        stringstream strstream;        strstream << "delete from stutable;";        cmd = strstream.str();        list<CStudentDTO>::iterator p;        for(p = mylist.begin();p!=mylist.end();p++)          {               strstream << "insert into stutable values (" << p->GetID() << ",'"<< p->GetName() <<"',"<< p->GetChineseScore() <<","<<p->GetEnglishScore()<< ");";            cmd = strstream.str();        }        nRows = db.execDML(cmd.c_str());//nRows:表示影响的行数        cout << nRows << " rows updated" << endl;        db.close();    }    catch (CppSQLite3Exception& e)    {        cerr << e.errorCode() << ":" << e.errorMessage() << endl;    }}

void MyDataBaseDAO::Read(list<CStudentDTO> &mylist){    try{        CppSQLite3DB db;        TCHAR path[255] = {0};        GetModuleFileName(NULL,path,255);        (_tcsrchr(path,'\\'))[1]='\0';        string sd = path;        sd = sd + _T("test.db");        string ssss(sd.begin(),sd.end());        //cout<<"SQLiteVersion:"<<db.SQLiteVersion()<<endl;        char *pppp = (char*)sd.c_str();        db.open(ssss.c_str());        //db.open("C:\\Users\\drilistbox\\Desktop\\test.db");        CppSQLite3Buffer bufSQL;        bufSQL.format("select * from stutable;");        CppSQLite3Query query = db.execQuery(bufSQL);        while (!query.eof())        {mylist.push_back(CStudentDTO(query.getIntField(0),query.getStringField(1),query.getFloatField(2),query.getFloatField(3)));            query.nextRow();        }        query.finalize(); //清除query的储存空间，否则内存泄漏        db.close();    }    catch (CppSQLite3Exception& e)    {        cerr << e.errorCode() << ":" << e.errorMessage() << endl;    }}