Delphi download file Android with Memory Stream

Question

I am trying to download a file from a server in this way:

var MeS:TMemoryStream;
begin
 Mes:=TMemoryStream.Create;
 IdFTP1.Connect;
 Mes.Position:=0;
  try
   IdFTP1.Get(Mes, 'dolcestilnovo.txt', True, False);
  finally
   MeS.Free;
   IdFTP1.Disconnect;
  end;
 Memo5.Lines.LoadFromStream(Mes);
end;

I must show the content of dolcestilnovo.txt inside that Memo5, but I have an error on the IdFTP1.Get(); method.

The error says "There is no overloaded version of 'Get' that can be called with these parameters". What can I do?

I thought to use the MemoryStream since I'm downloading it on an android device.

Just a side note, you are trying to populate the memo with the contents of a freed memory stream. — LU RD, Sep 25 '13 at 19:33
From what I can see, Get(string,TStream,boolean) is the overload to use here. — LU RD, Sep 25 '13 at 19:51
Your `Mes.Position:=0` is pointless there. It's an empty stream! — David Heffernan, Sep 25 '13 at 19:58
The `Mes.Free` is also in the wrong place. You are freeing the stream before it is loaded into the Memo. — Remy Lebeau, Sep 25 '13 at 20:36
Here's a tip for you in the future: Once you type `Something.Free;`, it's almost always wrong to type `Something.` again until you create it again. Once you `Free` it, it isn't able to be used any longer. — Ken White, Sep 25 '13 at 22:13

Remy Lebeau · Accepted Answer · 2013-09-25T20:36:11.677

6

Look at the signature of the TStream version of TIdFTP.Get():

procedure Get(const ASourceFile: string; ADest: TStream; AResume: Boolean = false); overload;

See why your code does not match it? Use this instead:

IdFTP1.Get('dolcestilnovo.txt', Mes, False);

And do not forget to reset the TMemoryStream.Position back to 0 again before calling Memo5.Lines.LoadFromStream(Mes) or else it will not load anything.

Try this:

var
  MeS: TMemoryStream;
begin
  Mes := TMemoryStream.Create;
  IdFTP1.Connect;
  try
    IdFTP1.Get('dolcestilnovo.txt', Mes, False);
  finally
    IdFTP1.Disconnect;
  end;
  Mes.Position := 0;
  Memo5.Lines.LoadFromStream(Mes);
end;

edited Sep 25 '13 at 20:36

answered Sep 25 '13 at 19:57

Remy Lebeau

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so when I end the try-catch statement I put a Mes.Position:=0 ? – Alberto Rossi Sep 25 '13 at 20:12
Doesn't the memory stream have to be free'd? – Jerry Dodge Sep 26 '13 at 03:28
@JerryDodge, ARC is implemented on the Android platform. No need to free objects. Confusing, yes I know and will mess up many code snippets in the future since it invalidates almost two decades of code. – LU RD Sep 26 '13 at 07:21

Delphi download file Android with Memory Stream

1 Answers1