Delphi database acces data from a datasource

Question

I've build a dataset in Delphi in which I have a ADOQuery that selectes 2 colums from a table... I drag and dropped a column from that ADOQuery into a form, how can I Acces my values from that column. I want to put that values into the combobox.

unit SCArabica;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, DB, Mask, DBCtrls, Grids, DBGrids;

type
  TForm1 = class(TForm)
ComboBox1: TComboBox;
    DBGrid1: TDBGrid;
    Label9: TLabel;
    DBEdit1: TDBEdit;
    DataSource1: TDataSource;
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  published
  end;

var
  Form1: TForm1;
implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin

end;

end.

DATASET Code

unit SCArabicaDataSet;

interface

uses
  SysUtils, Classes, FMTBcd, DB, SqlExpr, ADODB;

type
  TDataModule1 = class(TDataModule)
    ad: TADOConnection;
    ADOQuery1: TADOQuery;
    ADOQuery1CategoriePermisID: TIntegerField;
    ADOQuery1Categorie: TWideStringField;
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  DataModule1: TDataModule1;

implementation

{$R *.dfm}

end.

I'm new with Delphi can you guide me to some tutorials on how to build a program in Delphi that acces databases?

Answer 1

In my opinion, a good design would be to add a method in TDataModule1 to fetch records from the dataset and fill a TStrings. Then from the main code, you simply pass combobox.items.

procedure TDataModule1.FetchRecords(OutStrings : TStrings);
begin
    ADOQuery1.SQL.Text := 'SELECT COMPANY FROm COMPANIES WHERE COUNTRY="BELGIUM"';
    ADOQuery1.Open;
    while not ADOQuery1.Eof do begin
        OutStrings.Add(ADOQuery1.Fields[0].AsString;
        ADOQuery1.Next;
    end;
end;

Then you can write code in the form:

ComboBox1.Items.Clear;
DataModule1.FetchRecords(ComboBox1.Items);

I just typed this out of my head, so maybe some minor error, but you get the idea...

Answer 2

 while not dm1.ADOQuery2.Eof do
        begin
             DBComboBox1.Items.Add(dm1.ADOQuery2.Recordset.Fields['IDMasina'].Value) ;
             dm1.ADOQuery2.Next;
        end;

This is my solution.

dm1 is a DataSource
ADOQuery2 is a DataSet