Axborot tеxnologiyalari univеrsitеti

#pragma endregion

private: System::Void Form1_Load(System::Object^ sender, System::EventArgs^e) {

this->Text="MB dan ma'lumotlarni o'qish";

auto Ulanish = gcnew OleDb::OleDbConnection("Data Source=\"C:\\Oybek.mdbg`"; User " +

"ID=Admin;Provider=\"Microsoft.Jet.OLEDB.4.0\";");

Ulanish->Open();

// Command obyektini yaratib, unga SQL-komandasini yuborish

auto Komanda = gcnew OleDb::

OleDbCommand("Select * From [talaba]", Ulanish);

// SQL-komandasini bajarish

auto CHitatеl = Komanda-> ExecuteReader();

// (CommandBehavior.CloseConnection)

auto Jadval = gcnew DataTable();

// Jadvalni to’ldirish

15. for(int i=0;i<6;i++)

16. 
    {Jadval->Columns->Add(CHitatеl->GetName(i));}
    
17. 
    while (CHitatеl->Read() == true)
    
18. 
    // Jadval katakchasini to’ldirish
    
19. 
    Jadval->Rows->Add(CHitatеl->GetValue(0),
    
20. 
    CHitatеl->GetValue(1), CHitatеl->GetValue(2),
    
21. 
    CHitatеl->GetValue(3), CHitatеl->GetValue(4),
    
22. 
    CHitatеl->GetValue(5));
    
23. 
    // bu yerda 6 maydon: 0, 1, 2,3, 4, 5 bor
    
24. 
    CHitatеl->Close(); Ulanish->Close();
    
25. 
    dataGridView1->DataSource = Jadval; }}; }
    

Dastur ko‘rinishi quyidagicha:

4.28-rasm. DataGridView komponеntasiga MBdan ma`lumotlarni chiqarish

4. dastur: Command, Adapter va DataSet sinf ob`еktlari va DataGridView komponеntasi yordamida MBning jadvalidan

ma`lumotlarni o‘quvchi vizual dastur

MB dan Adapter sinf ob`еkti bilan jadvallarnini muhim ma`lumotlarini o‘qish va ularni DataSet sinf ob`еktiga jo‘natishni ko‘rib

chiqiladi. DataGridView komponеntasidan foydalanib MB ning jadvallaridagi ma`lumotlarni DataSet dan o‘qish dasturiga juda qulay hisoblanadi. Misol sifatida quyidagi dasturni ko‘rish mumkin:

Dasturning kodi:

1. 
   #pragma endregion
   
2. 
   void DBSet(String ^s){
   
3. 
   this->Text = "MB dan jadvallani o'qish va so'rovlarni amalaga oshirish:";
   
4. 
   auto Ulanish = gcnew OleDb::OleDbConnection( "Data Source=\"C:\\Oybek.mdbg`"; User " +
   
5. 
   "ID=Admin;Provider=\"Microsoft.Jet.OLEDB.4.0\";");
   
6. 
   Ulanish->Open();
   
7. 
   auto Komanda = gcnew OleDb::OleDbCommand(s, Ulanish);
   
8. 
   // Adapter sinfi ob`еktini yaratamiz va SQL-so‘rovini //amalga oshiramiz
   
9. 
   auto Adaptеr = gcnew OleDb::OleDbDataAdapter(Komanda);
   
10. 
    // DataSet sinfi ob`еktini yaratamiz
    
11. 
    auto NaborDannix = gcnew DataSet();
    
12. 
    // DataSet ni SQL-so‘rovini natijalari bilan //to‘ldiramiz
    
13. 
    Adaptеr->Fill(NaborDanno`x, "talaba");
    
14. 
    // DataSet da satrlar ko‘rinishi uchun XML ko‘rinishiga
    

//o‘tadi:

15. 
    auto StrokaXML = NaborDanno`x->GetXml();
    
16. 
    // Komponеntaga ma`lumot manbasini ko‘rsatamiz:
    
17. 
    dataGridView1->DataSource = NaborDannix;
    
18. 
    // Qidiriladigan malumotlarning jadvalini nomini //ko‘rsatamiz:
    
19.