Как сделать ADO-connection

uses
 ComObj;

function OpenConnection(ConnectionString: AnsiString): Integer;
var
 ADODBConnection: OleVariant;
begin
 ADODBConnection := CreateOleObject('ADODB.Connection');
 ADODBConnection.CursorLocation := 3; // User client
 ADODBConnection.ConnectionString := ConnectionString;
 Result := 0;
 try
 ADODBConnection.Open;
 except
 Result := -1;
 end;
end;

function DataBaseConnection_Test(bMessage: Boolean): AnsiString;
var
 asTimeout, asUserName, asPassword, asDataSource, ConnectionString: AnsiString;
 iReturn: Integer;
 OldCursor: TCursor;
begin
 OldCursor := Screen.Cursor;
 Screen.Cursor := crHourGlass;
 asTimeout := '150';
 asUserName := 'NT_Server';
 asPassword := 'SA';
 asDataSource := 'SQL Server - My DataBase';

 ConnectionString := 'Data Source = ' + asDataSource +
 'User ID = ' + asUserName +
 'Password = ' + asPassword +
 'Mode = Read|Write;Connect Timeout = ' + asTimeout;
 try
 iReturn := OpenConnection(ConnectionString);

 if (bMessage) then
 begin
 if (iReturn = 0) then
 Application.MessageBox('Connection OK!', 'Information', MB_OK)
 else if (iReturn = -1) then
 Application.MessageBox('Connection Error!', 'Error', MB_ICONERROR +
 MB_OK);
 end;

 if (iReturn = 0) then
 Result := ConnectionString
 else if (iReturn = -1) then
 Result := '';
 finally
 Screen.Cursor := OldCursor;
 end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
 DataBaseConnection_Test(True);
end