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copied!<p>There's no need for two columns here.</p> <p>You can take advantage of the fact that <code>TComboBox.Items</code> (like many other things in Delphi, like <code>TStringList</code>, <code>TMemo.Lines</code>, and <code>TListBox.Items</code>) descends from <code>TStrings</code>, which has both the <code>Strings</code> and <code>Objects</code> properties. <code>Objects</code> stores anything the size of a <code>TObject</code>, which is a pointer.</p> <p>This means you can store your integer value by simply typecasting it to a <em>TObject</em> when adding it, and typecasting it back to an <em>Integer</em> when retrieving it.</p> <p>Something like this should work:</p> <pre><code>procedure TForm1.FormCreate(Snder: TObject); var i: Integer; sItem: String; begin for i := 0 to 9 do begin sItem := Format('Item %d', [i]); ComboBox1.Items.AddObject(sItem, TObject(i)); end; end; </code></pre> <p>To retrieve the value:</p> <pre><code>procedure TForm1.ComboBox1Click(Sender: TObject); var Idx: Integer; Value: Integer; begin Idx := ComboBox1.ItemIndex; if Idx <> -1 then begin Value := Integer(ComboBox1.Items.Objects[Idx]); // Do something with value you retrieved end; end; </code></pre> <p>Note that, since the <em>Objects</em> property is actually meant to store <em>objects</em>, this gives you a lot of flexibility. Here's an example (intentionally very trivial) of storing a customer's contact information in an associated object instance and displaying it in labels when an item from a listbox is selected.</p> <pre><code>unit Unit1; interface uses Windows, Messages, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TCustomer=class private FContact: string; FPhone: string; public constructor CreateCustomer(const AContact, APhone: string); property Contact: string read FContact write FContact; property Phone: string read FPhone write FPhone; end; TForm1 = class(TForm) ListBox1: TListBox; Label1: TLabel; Label2: TLabel; Label3: TLabel; lblContact: TLabel; lblPhone: TLabel; procedure FormCreate(Sender: TObject); procedure FormClose(Sender: TObject; var Action: TCloseAction); procedure ListBox1Click(Sender: TObject); private { Private declarations } public { Public declarations } end; var Form1: TForm1; implementation {$R *.dfm} { TCustomer } constructor TCustomer.CreateCustomer(const AContact, APhone: string); begin inherited Create; FContact := AContact; FPhone := APhone; end; procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction); var i: Integer; begin for i := 0 to ListBox1.Items.Count - 1 do ListBox1.Items.Objects[i].Free; end; procedure TForm1.FormCreate(Sender: TObject); begin lblContact.Caption := ''; lblPhone.Caption := ''; // Create some customers. Of course in the real world you'd load this // from some persistent source instead of hard-coding them here. ListBox1.Items.AddObject('N Company', TCustomer.CreateCustomer('Nancy', '555-3333')); ListBox1.Items.AddObject('B Company', TCustomer.CreateCustomer('Brad', '555-1212')); ListBox1.Items.AddObject('A Company', TCustomer.CreateCustomer('Angie', '555-2345')); end; procedure TForm1.ListBox1Click(Sender: TObject); var Cust: TCustomer; begin if ListBox1.ItemIndex <> -1 then begin Cust := TCustomer(ListBox1.Items.Objects[ListBox1.ItemIndex]); lblContact.Caption := Cust.Contact; lblPhone.Caption := Cust.Phone; end; end; end. </code></pre>

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