Listen on Blocknative's mempool WebSocket API

Unit1.pas

var
  Mempool: IMempool;

procedure TForm1.Button1Click(Sender: TObject);
begin
  Mempool := TSgcMempool.Subscribe(
    Mainnet,                                      // ethereum main net
    'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx',       // your blocknative API key
    '0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48', // address to watch
    procedure(event: TJsonObject; err: IError)    // continuous events (or a blocknative error)
    begin
      var tx := web3.eth.blocknative.mempool.getTransaction(event);
      if Assigned(tx) then
        TThread.Synchronize(nil, procedure
        begin
          Memo1.Lines.Add(tx.ToString);
        end);
    end,
    procedure(err: IError) // non-blocknative-error handler (probably a socket error)
    begin
      TThread.Synchronize(nil, procedure
      begin
        MessageDlg(err.Message, TMsgDlgType.mtError, [TMsgDlgBtn.mbOK], 0);
      end);
    end,
    procedure
    begin
      // connection closed
    end);
end;