Building an IRC Client

This event handler processes every single command that comes from the server.

procedure TForm1.IdIRC1ServerListReceived(ASender: TIdContext;

  AServerList: TStrings);

 var

  i:integer;

begin

for i:= 0 to AServerList.Count-1 do begin

memo1.lines.add(AServerList.Strings[i]);

end;

end;

This event is fired when you receive a list of server names.

procedure TForm1.IdIRC1ServerWelcome(ASender: TIdContext;

  AWelcomeInfo: TStrings);

var

  i:integer;

begin

for i:= 0 to AWelcomeInfo.Count-1 do begin

memo1.lines.add(AWelcomeInfo.Strings[i]);

end;

end;

procedure TForm1.IdIRC1ServerVersion(ASender: TIdContext;
Version, Host,

  Comments: String);

begin

memo1.Lines.Add(Version +'Host '+Host+'Comments '+Comments);

end;

procedure TForm1.Edit2Click(Sender: TObject);

begin

button1.Enabled:=true;

end;

procedure TForm1.Edit3Click(Sender: TObject);

begin

button1.Enabled:=true;

end;

procedure TForm1.IdIRC1MOTD(ASender: TIdContext; AMOTD:
TStrings);

var

  i:integer;

begin

for i:= 0 to AMOTD.Count-1 do begin

memo1.lines.add(AMOTD.Strings[i]);

end;

end;

procedure TForm1.IdIRC1UserInfoReceived(ASender: TIdContext;

  AUserInfo: TStrings);

var

  i:integer;

begin

for i:= 0 to AUserInfo.Count-1 do begin

memo1.lines.add(AUserInfo.Strings[i]);

end;

end;

procedure TForm1.Button3Click(Sender: TObject);

begin

 idIRC1.Join(edit3.text);

//after joining you can request the names of the channels here,
using the ListChannel() //function and then displaying the names
in a memo.

end;

procedure TForm1.IdIRC1NicknamesListReceived(ASender: TIdContext;

  AChannel: String; ANicknameList: TStrings);

var

  i:integer;

begin

memo1.Lines.Add('Nicknames in Channel: '+AChannel);

for i:= 0 to ANicknameList.Count-1 do begin

memo1.lines.add(ANicknameList.Strings[i]);

end;

end;

This event fires when you receive a list of nicknames in a channel. The list itself is returned by the ListChannelNicknames() procedure. You also get other info such as the channel name.

procedure TForm1.IdIRC1ServerUsersListReceived(ASender:
TIdContext;

  AUsers: TStrings);

var

  i:integer;

begin

for i:= 0 to AUsers.Count-1 do begin

memo1.lines.add(AUsers.Strings[i]);

end;

end;

procedure TForm1.IdIRC1NicknameError(ASender: TIdContext; AError:
Integer);

begin

//here you get the error number(stored in AError above) and find
the error that corresponds to the number.

end;

The last three procedures just make the GUI fun by setting the progress bar position whenever the client does any work.

procedure TForm1.IdIRC1Work(ASender: TObject; AWorkMode:
TWorkMode;

  AWorkCount: Integer);

begin

 progb.Position:=AWorkCount;

end;

procedure TForm1.IdIRC1WorkBegin(ASender: TObject; AWorkMode:
TWorkMode;

  AWorkCountMax: Integer);

begin

progb.Max:=AWorkCountMax;

end;

procedure TForm1.IdIRC1WorkEnd(ASender: TObject; AWorkMode:
TWorkMode);

begin

progb.Position:=progb.Max;

end;

Below is a screen shot of the client in action:

Conclusion

I've shown you all the commands that this client application will implement. It is by no means all of the commands available, but it should give you the basis and inspiration to continue working through all the remaining commands.