Как создать поле Lookup во время выполнения приложения?

Code:

uses

Forms, Classes, Controls, StdCtrls, Db, DBTables, DBCtrls;

type

TForm1 = class(TForm)

   Table1: TTable;   // DBDemos customer table

   Table2: TTable;   // DBDemos orders table

   Button1: TButton;

   DBLookupComboBox1: TDBLookupComboBox;

   DataSource1: TDataSource;

   Table2CustNo: TFloatField;  // CustNo key field object used for Lookup  

   procedure Button1Click(Sender: TObject);

private

   { Private declarations }

public

   { Public declarations }

end;

var

Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);

begin

with TStringField.Create(Table2) do begin

   FieldName := 'MyLookup';

   FieldKind:= fkLookup;

   DataSet := Table2;  

   Name := Dataset.Name + FieldName;

   KeyFields:= 'CustNo';

   LookUpDataset:= Table1;

   LookUpKeyFields:= 'CustNo';

   LookUpResultField:= 'Company';

   DbLookupCombobox1.DataField:= FieldName;

   DataSource1.DataSet:= Dataset;

   Table2.FieldDefs.Add(Name, ftString, 20, false);

end;

DbLookupCombobox1.DataSource:= Datasource1;

Table1.Active:= True;

Table2.Active:= True;

end;

end.