Question

How can I properly free the component once i make it with a loop like this? If I free it like I do now I get some GETMEM.INC exception. I am coming from Indy so i don’t really know ICS too much.

Thanks

  const
    URLs : array[0..3] of string =
    (
      'http://www.example.com',
      'http://www.example.com',
      'http://www.example.com',
      'http://www.example.com'
    ) ;

    var
      Output: array of TStringList;
      S: array of TMemoryStream;
      Async: array of TSslHttpCli;
    implementation

    procedure RequestDone(Sender: TObject; RqType: THttpRequest;
      ErrCode: Word);
    begin
        with Sender as TSSLHTTPCLI do  begin
          S[Tag].Position:=0;
          Output[Tag].LoadFromStream(S[Tag]);
        end;
      end;


    procedure TForm1.Button1Click(Sender: TObject);
    var
    i:integer;
    begin
        for i := 0 to High(URLS) do begin
           S[i]:=TMemoryStream.Create;
           Output[i]:=TStringList.Create;
           Async[i]:=TSslHttpCli.Create(nil);
           Async[i].Tag:=i;
           Async[i].FollowRelocation:=true;
           Async[i].NoCache:=true;

           Async[i].SocketFamily:=sfAny;
           Async[i].OnRequestDone:=RequestDone;
           Async[i].RcvdStream:=S[i];
           Async[i].URL:= URLs[i];
           Async[i].MultiThreaded:=true;
           Async[i].GetASync;
        end;
    end;

    procedure TForm1.Button4Click(Sender: TObject);
    var
    i:integer;
    begin
        for i := 0 to High(URLS) do begin
           Output[i].Free;
           Async[i].RcvdStream.Free;
           Async[i].Free; // << -- EXCEPTION
           //  S[i].Free;
        end;
    end;

Answer 1

You never allocate any memory for Result, Asynch, or S. You need to SetLength on each of them before you can put anything into them (or take anything back out).

procedure TForm1.Button1Click(Sender: TObject);
var
i:integer;
begin
  SetLength(Result, Length(URLS));
  SetLength(S, Length(URLS));
  SetLength(Asynch, Length(URLS));

  for i := 0 to High(URLS) do begin
    S[i]:=TMemoryStream.Create;
    Result[i]:=TStringList.Create;
    Async[i]:=TSslHttpCli.Create(nil);

    // etc.

  end;
end;

BTW, Result is a terrible name for a variable, especially one that’s global in scope. It’s the return value from a function that’s automatically generated by the compiler, and use anywhere but in a function makes your code hard to read. See this, for instance:

var
  Result: string = '';

procedure AddToReslt(CharToAdd: Char);
begin
  // Many many lines of code
  // go in here. Maybe a few loops
  // of if statements.
  Result := Result + CharToAdd;
end;

function DoSomeMath: Integer;
begin
  // Some really complex numeric code, maybe
  // calculating the value of `pi` to the 900th
  // digit 
  Result := 2 * 2;
end;

Now quickly – remembering that each of them containss lots of code – which one is a function and which is a procedure?