Wie erkenne ich die Enter-Taste in ein edit-Feld?

Habe ich einen UDP-messenger mit einem Senden-button, aber es ärgert mich, dass ich auf den Knopf drücken, anstatt einfach nur schlagen Enter. So habe ich erstellt Prozedur TForm1.Edit2KeyPress. Nun habe ich keine Ahnung, wie definieren Sie die Enter-Taste in if (enter is pressed) then {code for sending message}.

Nach der Beantwortung habe ich ein neues problem. Alles, was ich geben ist , sended, Brief.. hier ist mein code
Einheit chat1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, IdSocketHandle, StdCtrls;

type
  TForm1 = class(TForm)
   Button1: TButton;
   Memo1: TMemo;
Edit1: TEdit;
Button2: TButton;
Edit2: TEdit;
Label1: TLabel;
procedure Button1Click(Sender: TObject);
procedure FormActivate(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Edit2KeyPress(Sender: TObject; var Key: Char);
private
Activated: Boolean;
procedure SearchEvent(ResultIP, ResultName: String);
procedure UDPRead(Sender: TObject; AData: TStream;
  ABinding: TIdSocketHandle);
procedure UDPException(Sender: TObject);
public
end;

var
Form1: TForm1;
ss:string  ;

implementation

uses UDP;

{$R *.dfm}



procedure TForm1.Button1Click(Sender: TObject);
begin
  UDPSearchForm.SearchEvent := SearchEvent;
  UDPSearchForm.Left := Left;
  UDPSearchForm.Top := Top;
  UDPSearchForm.AktIP := Edit1.Text;
UDPSearchForm.SearchPartner;
end;

procedure TForm1.SearchEvent(ResultIP, ResultName: String);
begin
  Edit1.Text := ResultIP;
  Label1.Caption := ResultName;
end;

procedure TForm1.FormActivate(Sender: TObject);
var
  s, s2: String;
begin
  if Activated then exit;
  Memo1.Clear;
  Activated := true;
  UDPSearchForm.OnUDPRead := UDPRead;
  UDPSearchForm.OnException := UDPException;
  UDPSearchForm.Active := true;
  s := UDPSearchForm.LocalAddress;
  s2 := UDPSearchForm.WSGetHostByAddr(s);
  Memo1.Lines.Add('I''m (' + s + ') ' + s2);
end;

procedure TForm1.UDPRead(Sender: TObject; AData: TStream;
   ABinding: TIdSocketHandle);
var
  Buffer: Array [0..2047] of Byte;
  count: Integer;
  PeerIP: String;
  PeerPort: Integer;
  s: String;
  i: Integer;
begin
  PeerIP := ABinding.PeerIP;
  PeerPort:= ABinding.PeerPort;
  count := AData.Size;
  if count > Length(Buffer) then begin
    exit;
  end;
  AData.Read(Buffer, count);
  if (Buffer[0] <> $00) and  (Buffer[0] <> $01) then begin  // not search
    Edit1.Text:= PeerIP;
  end;
  case Buffer[0] of
   $00: begin   // search request
    case count of
     4: begin
      case Buffer[1] of
       0: begin
        Buffer[0] := $01;
         UDPSearchForm.Host := PeerIP;
         UDPSearchForm.DoSend(Buffer, 4, Length(Buffer));
        Memo1.Lines.Add('Inquiry [' + UDPSearchForm.WSGetHostByAddr(PeerIP) + '(' +     PeerIP + ')' +          ' Port: ' + IntToStr(PeerPort) +
      ']');
   end;
  end;
 end;
end;
   end;
   $01: begin // Search Reply
    case count of
     4: begin
      case Buffer[1] of 0:
        begin
        ss := UDPSearchForm.WSGetHostByAddr(PeerIP);
    s := '[' + ss + '(' + PeerIP + ')' +
      ' Client Port: ' + IntToStr(PeerPort) +
      ']';
    Memo1.Lines.Add('Inquiry Reply ' + s);
    if PeerIp = UDPSearchForm.LocalAddress then begin
      ss := '<myself>' + ss;
    end;
    UDPSearchForm.Add(PeerIP, ss);
    end;
   end;
  end;
 end;
end;
    $10: begin // Text
     case Buffer[1] of
      0: begin
       s := '';
           for i := 4 to count-1 do begin
             s := s + char(Buffer[i]);
           end;
       Memo1.Lines.Add(ss+'  says: ' + s);
      end;
     end;
    end;
  end;
end;

procedure TForm1.UDPException(Sender: TObject);
begin
  //nothing
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  x: Array[0..100] of Byte;
  i: Integer;
begin
  UDPSearchForm.Host := Edit1.Text;
  UDPSearchForm.Active := true;
  x[0] := $10; // Text
  x[1] := 0;   // Type 0
  for i := 1 to Length(Edit2.Text) do begin
    x[i+3] := Byte(Edit2.Text[i]);
  end;
  UDPSearchForm.DoSend(x, 4+Length(Edit2.Text), length(x));

   Memo1.Text:=Memo1.Text+Edit2.Text+#13#10;
end;

procedure TForm1.Edit2KeyPress(Sender: TObject; var Key: Char);
var
  x: Array[0..100] of Byte;
  i: Integer;
begin
if Ord(Key) = VK_RETURN then
  UDPSearchForm.Host := Edit1.Text;
  UDPSearchForm.Active := true;
  x[0] := $10; // Text
  x[1] := 0;   // Type 0
  for i := 1 to Length(Edit2.Text) do begin
    x[i+3] := Byte(Edit2.Text[i]);
  end;
  UDPSearchForm.DoSend(x, 4+Length(Edit2.Text), length(x));

   Memo1.Text:=Memo1.Text+Edit2.Text+#13#10;


end;

end.