Delphi ActiveX Requires Chilkat v11.0.0+

Transfer a File using Sockets (TLS or non-TLS)

See more Socket/SSL/TLS Examples

Demonstrates how to two programs, one a socket writer and the other a socket reader, can transfer a file. The connection can be TLS or a regular non-encrypted TCP connection. Delphi ActiveX

var
success: Integer;
bdToSend: TChilkatBinData;
sndSock: TChilkatSocket;
bUseTls: Integer;
port: Integer;
maxWaitMs: Integer;
numBytes: Integer;
bBigEndian: Integer;
listenSock: TChilkatSocket;
rcvSock: TChilkatSocket;
numBytesComing: Integer;
bdReceived: TChilkatBinData;
maxWaitMs: Integer;

begin
success := 0;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  On the sending side, we'll load the file into a BinData object and send.
//  On the receiving side, we'll read from the socket connection into a BinData, and save to a file.
//  This example assumes the file is not crazy-large, and that the entire contents
//  can fit into memory.  
//  (If the file is too large for memory, there are other ways to send. It just involves streaming or 
//  sending the file chunk-by-chunk..)

//  This section of code is for the sender.
bdToSend := TChilkatBinData.Create(Self);
success := bdToSend.LoadFile('somePath/someFile.dat');
//  Assume success for the example...

sndSock := TChilkatSocket.Create(Self);
bUseTls := 1;
port := 5555;
maxWaitMs := 5000;
success := sndSock.Connect('some_domain_or_ip.com',port,bUseTls,maxWaitMs);
//  Assume success for the example...

//  Tell the receiver how many bytes are coming.
numBytes := bdToSend.NumBytes;
bBigEndian := 1;
success := sndSock.SendInt32(numBytes,bBigEndian);

//  Send the file data (sends the entire contents of bdToSend).
success := sndSock.SendBd(bdToSend.ControlInterface,0,0);

//  Get an acknowledgement.
success := sndSock.ReceiveInt32(bBigEndian);
if (success = 0) then
  begin
    Memo1.Lines.Add(sndSock.LastErrorText);
    Exit;
  end;

//  Did the receiver get the correct number of bytes?
if (sndSock.ReceivedInt <> numBytes) then
  begin
    Memo1.Lines.Add('The receiver did not acknowledge with the correct number of bytes.');
    Exit;
  end;

Memo1.Lines.Add('File sent!');

//  ------------------------------------------------------------------------------------
//  The code below is for the receiving side (running on some other computer..)

listenSock := TChilkatSocket.Create(Self);

success := listenSock.BindAndListen(5555,25);
if (success = 0) then
  begin
    Memo1.Lines.Add(listenSock.LastErrorText);
    Exit;
  end;

//  Get the next incoming connection
//  Wait a maximum of 20 seconds (20000 millisec)
rcvSock := TChilkatSocket.Create(Self);
success := listenSock.AcceptNext(20000,rcvSock.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(listenSock.LastErrorText);
    Exit;
  end;

//  The sender will first send the big-endian integer for the number of bytes
//  that are forthcoming..
success := rcvSock.ReceiveInt32(bBigEndian);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rcvSock.LastErrorText);
    Exit;
  end;

numBytesComing := rcvSock.ReceivedInt;

//  Receive that many bytes..
bdReceived := TChilkatBinData.Create(Self);
success := rcvSock.ReceiveBdN(numBytesComing,bdReceived.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rcvSock.LastErrorText);
    Exit;
  end;

//  Acknowledge the sender by sending back the number of bytes we received.
success := rcvSock.SendInt32(bdReceived.NumBytes,bBigEndian);

//  Close the connection.
maxWaitMs := 20;
rcvSock.Close(maxWaitMs);

//  Save the received data to a file.
success := bdReceived.WriteFile('somePath/someFile.dat');
//  Assume success for the example...

Memo1.Lines.Add('File received!');