Please help how to send images from client to server? - delphi

Question

This is my server's coding
procedure TForm1.IdTCPServerExecute(AThread: TIdPeerThread);
var
InputString: string;
ACommand: string[1];
AFileName: string;
ATempFileName: string;
AFileStream: TFileStream;
begin
InputString := UpperCase(AThread.Connection.ReadLn);
ACommand := Copy(InputString, 1, 1);
AFileName := FPicFilePath + Copy(InputString, 2, 5) + '.jpg';
if ACommand = 'R' then begin
AFileStream := TFileStream.Create(AFileName, fmOpenRead + fmShareDenyNone);
try
AThread.Connection.WriteStream(AFileStream, true, true);
finally
AFileStream.Free;
end;
end else if ACommand = 'S' then begin
ATempFileName := FPicFilePath + 'TEMP.jpg';
if FileExists(ATempFileName) then
DeleteFile(ATempFileName);
AFileStream := TFileStream.Create(ATempFileName, fmCreate);
try
AThread.Connection.ReadStream(AFileStream, -1, false);
//RenameFile(ATempFileName, AFileName);
finally
AFileStream.Free;
end;
end;
AThread.Connection.Disconnect;
end;
And this is my client's coding
procedure TForm1.SendImageToServer(ASendCmd: string);
var
AFileStream: TFileStream;
begin
MessageDlg('Sending ' + ASendCmd + ' :' + FSendFileName, mtInformation, [mbOK], 0);
Screen.Cursor := crHourGlass;
with IdTCPClient do begin
if Connected then Disconnect;
Host := '127.0.0.1';
Port := 2108;
AFileStream := TFileStream.Create(FSendFileName, fmOpenRead);
try
try
Connect;
try
WriteLn(ASendCmd);
WriteStream(AFileStream, true, false);
finally
Disconnect;
end;
finally
AFileStream.Free;
end;
except
end;
end;
Screen.Cursor := crDefault;
end;
I can successfully get images from server, but when I had to send a new image back to server, I just had an empty TEMP.jpg.
Please help.
Thanks.
Delphi 5, Indy 9

Answer 1

When sending a file from the client to the server, the client is not telling WriteStream() to send the stream size, but the server is telling ReadStream() to expect the stream size to arrive, so you have a mismatch.
When sending a file from the server to the client, the server is telling WriteStream() to send the stream size, and the client is telling ReadStream() to expect the stream size to arrive, so there is no mismatch.