TBaseSocket.ReceiveBuf Method

Reads data buffers to the socket.

Pascal

function ReceiveBuf(var Buf; BufSize: Integer; Flags: Integer = 0): Integer;

C++

__fastcall int ReceiveBuf( Buf, int BufSize, int Flags = 0);

Description

ReceiveBuf reads data buffers of size bufsize to the socket. Use buf to assign a variable to the buffer, and use bufsize to set the size of the buffer to be read. The flags argument can be any of the flags used by the Linux recv function. Refer to recv(2) in the Linux manual pages for more information.

C++ Examples:

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/*
This example demonstrated the use of TTcpServer in order to receive
a buffer (stream) and process it. It is to be used with the example
from TTcpClient section.
This example uses three buttons, one for activating the server, one
for deactivating it and the third for clearing the Memo.
*/
__fastcall TForm3::TForm3(TComponent* Owner)
    : TForm(Owner)
{
    Memo1->Lines->Clear();

    //server initialization
    TcpServer1 = new TTcpServer(this);
    TcpServer1->OnAccept = TcpServer1Accept;
    TcpServer1->OnCreateHandle = TcpServer1CreateHandle;
    TcpServer1->OnDestroyHandle = TcpServer1DestroyHandle;

}
//---------------------------------------------------------------------------
void __fastcall TForm3::TcpServer1Accept(TObject *Sender,
                                        TCustomIpClient *ClientSocket)
{
    byte a[10];
    ClientSocket->ReceiveBuf(a,10,0);
    TDateTime now = TDateTime::CurrentDateTime();
    Memo1->Lines->Add(DateTimeToStr(now) + " Data added width " +
                        IntToStr(a[9]));
    for (int i=0; i < 9; i++)
    {
        Memo1->Lines->Add(IntToStr(a[i] + a[9]));
    }
    Memo1->Lines->Add("--------------------");

}
//---------------------------------------------------------------------------
void __fastcall TForm3::Button1Click(TObject *Sender)
{
    TcpServer1->LocalPort = DEFAULT_PORT;
    TcpServer1->Active = true;
}
//---------------------------------------------------------------------------
void __fastcall TForm3::Button2Click(TObject *Sender)
{
    TcpServer1->Active = false;
}

//---------------------------------------------------------------------------
void __fastcall TForm3::Button3Click(TObject *Sender)
{
    Memo1->Lines->Clear();
}
//---------------------------------------------------------------------------

void __fastcall TForm3::TcpServer1CreateHandle(TObject *Sender)
{
    TDateTime now = TDateTime::CurrentDateTime();
    Memo1->Lines->Add(DateTimeToStr(now) + " Server started.");
}
//---------------------------------------------------------------------------

void __fastcall TForm3::TcpServer1DestroyHandle(TObject *Sender)
{
    TDateTime now = TDateTime::CurrentDateTime();
    if(this->Memo1)
    {
        Memo1->Lines->Add(DateTimeToStr(now) + " Server stopped.");
    }
}
//---------------------------------------------------------------------------

Delphi Examples:

Copy Code

{
This example demonstrated the use of TTcpServer in order to receive
a buffer (stream) and process it. It is to be used with the example
from TTcpClient section.
}

const DEFAULT_PORT = 2501;

{$R *.dfm}

procedure TForm3.Button1Click(Sender: TObject);
begin
  //connectiong the server
  TcpServer1.Active := true;
end;

procedure TForm3.Button2Click(Sender: TObject);
begin
  //disconnecting the server
  TcpServer1.Active := false;
end;

procedure TForm3.Button3Click(Sender: TObject);
begin
  //clearing the memo
  Memo1.Lines.Clear;
end;

procedure TForm3.FormCreate(Sender: TObject);
begin
  Memo1.Lines.Clear;

  //server initialization
  TcpServer1 := TTcpServer.Create(Self);
  TcpServer1.OnAccept := TCpServer1Accept;
  TcpServer1.OnCreateHandle := TcpServer1CreateHandle;
  TcpServer1.OnDestroyHandle := TcpServer1DestroyHandle;
  TcpServer1.LocalPort := IntToStr(DEFAULT_PORT);
end;

procedure TForm3.TcpServer1Accept(Sender: TObject;
  ClientSocket: TCustomIpClient);
var
  a : array[0..9] of byte;
  I : Cardinal;
begin

  ClientSocket.ReceiveBuf(a,10,0);
  Memo1.Lines.Add(DateTimeToStr(now) + ' Data added with ' +
                  IntToStr(a[9]));
  for I := 0 to 8 do
  begin
    Memo1.Lines.Add(IntToStr(a[I] + a[9]));
  end;
  Memo1.Lines.Add('--------------------');

end;

procedure TForm3.TcpServer1CreateHandle(Sender: TObject);
begin
  Memo1.Lines.Add(DateTimeToStr(now) + ' Server started.');
end;

procedure TForm3.TcpServer1DestroyHandle(Sender: TObject);
begin
  if Self.Memo1 <> nil then
    Memo1.Lines.Add(DateTimeToStr(now) + ' Server stopped.');
end;