Занести данные из столбца в ComboBox

sComboBox1->Items->Clear();
sComboBox1->Text = "";
String S = sListBox1->Items->Strings[sListBox1->ItemIndex];
for(int j=0;j<Form4->DBGrid1->DataSource->DataSet->RecordCount;j++)
        {
                sComboBox1->Items->Add(Form4->ADOQuery1->FieldByName(S)->AsString);
                Form4->ADOQuery1->Next();
        }
        Form4->ADOQuery1->First();

ADOQuery1->Close();
ADOQuery1->SQL->Clear();
ADOQuery1->SQL->Add("SELECT DISTINCT AutoCad FROM Glavnaya");
ADOQuery1->Open();
ADOQuery1->First();
while(!ADOQuery1->Eof)
{
  ComboBox1->Items->Add(MainForm->ADOQuery1->FieldByName("AutoCad")->AsString);
  MainForm->ADOQuery1->Next();
}
ADOQuery1->First();

 Form4->ADOQuery1->Close();
         String X = Form4->ADOQuery1->SQL->Text;
        Form4->ADOQuery1->SQL->Clear();
        Form4->ADOQuery1->SQL->Add("SELECT DISTINCT ["+S+"] FROM ["+Form4->ADOTable1->TableName+"]");
        Form4->ADOQuery1->Open();
        Form4->ADOQuery1->First();
        while(!Form4->ADOQuery1->Eof)
        {
        sComboBox1->Items->Add(Form4->ADOQuery1->FieldByName(S)->AsString);
        Form4->ADOQuery1->Next();
        }
        Form4->ADOQuery1->First();
        Form4->ADOQuery1->SQL->Text = X;
        Form4->ADOQuery1->Open();