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String vs. PChar

Posted on 2004-04-05
4
431 Views
Last Modified: 2010-04-05
procedure Foo(buffer: PChar);
begin
  ...
  // list: TStringList;
  list.Text := buffer;
  ...
end;

Am I allowed to free "buffer" after calling Foo, that is do I get a copy of the memory "buffer" points to?
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Question by:__alex
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4 Comments
 
LVL 26

Expert Comment

by:Russell Libby
ID: 10757496
Yes, you are allowed to free this buffer, as the memory for the list is allocated internally to the list

Regards,
Russell
0
 
LVL 26

Accepted Solution

by:
Russell Libby earned 125 total points
ID: 10757511
See the following (SetString in paticular):

procedure TStrings.SetTextStr(const Value: string);
var
  P, Start: PChar;
  S: string;
begin
  BeginUpdate;
  try
    Clear;
    P := Pointer(Value);
    if P <> nil then
      while P^ <> #0 do
      begin
        Start := P;
        while not (P^ in [#0, #10, #13]) do Inc(P);
        SetString(S, Start, P - Start);
        Add(S);
        if P^ = #13 then Inc(P);
        if P^ = #10 then Inc(P);
      end;
  finally
    EndUpdate;
  end;
end;

Russell
0
 
LVL 2

Author Comment

by:__alex
ID: 10757619
Thanks Russel!
0
 
LVL 26

Expert Comment

by:Russell Libby
ID: 10757660
You are very welcome, and thank you

Russell

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