Zip erstellen über Shell API

[ConstantGardener]

Hallo zusammen,

ich habe im Blog von TMS Software folgende Unit gefunden. Mit Ihr lassen sich die windowseigenen Zip_Funktionen zum komprimieren und dekomprimieren nutzen.
Sehr komfortabel wenn es funktionieren würde. Die Funktionen kompilieren unter D2010 und D2006 ohne Probleme. Er schmeißt mir aber eine Access Violation beim CopyHere in
der Funktion ShellZip.

Kann das mal einer von Euch testen ? Irgendwelche erleuchtenden Infos ?

Code:

unit ShellZip;

interface

 function NumProcessThreads: integer;
 function ShellZip(zipfile, sourcefolder:string; filter: string = ''): boolean;
 function ShellUnzip(zipfile, targetfolder: string; filter: string = ''): boolean;


implementation

uses Comobj, Windows,Tlhelp32;

const
  SHCONTCH_NOPROGRESSBOX = 4;
  SHCONTCH_AUTORENAME = 8;
  SHCONTCH_RESPONDYESTOALL = 16;
  SHCONTF_INCLUDEHIDDEN = 128;
  SHCONTF_FOLDERS = 32;
  SHCONTF_NONFOLDERS = 64;

function ShellUnzip(zipfile, targetfolder: string; filter: string = ''): boolean;
var
  shellobj: variant;
  srcfldr, destfldr: variant;
  shellfldritems: variant;
begin
  shellobj := CreateOleObject('Shell.Application');

  srcfldr := shellobj.NameSpace(zipfile);
  destfldr := shellobj.NameSpace(targetfolder);

  shellfldritems := srcfldr.Items;
  if (filter <> '') then
    shellfldritems.Filter(SHCONTF_INCLUDEHIDDEN or SHCONTF_NONFOLDERS or SHCONTF_FOLDERS,filter);

  destfldr.CopyHere(shellfldritems, SHCONTCH_NOPROGRESSBOX or SHCONTCH_RESPONDYESTOALL);
end;

function NumProcessThreads: integer;
var
  hsnapshot: THandle;
  Te32: TTHREADENTRY32;
  proch: dword;
  procthreads: integer;
begin
  procthreads := 0;

  proch := GetCurrentProcessID;

  hSnapShot := CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);

  Te32.dwSize := sizeof(TTHREADENTRY32);

  if Thread32First(hSnapShot, Te32) then
  begin
    if te32.th32OwnerProcessID = proch then
      inc(procthreads);

    while Thread32Next(hSnapShot, Te32) do
    begin
      if te32.th32OwnerProcessID = proch then
        inc(procthreads);
    end;
  end;
  CloseHandle (hSnapShot);
  Result := procthreads;
end;

function ShellZip(zipfile, sourcefolder:string; filter: string = ''): boolean;
const
  emptyzip: array[0..23] of byte  = (80,75,5,6,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0);
var
  ms: TMemoryStream;
  shellobj: variant;
  srcfldr, destfldr: variant;
  shellfldritems: variant;
  numt: integer;
begin
  if not FileExists(zipfile) then
  begin
    // create a new empty ZIP file
    ms := TMemoryStream.Create;
    ms.WriteBuffer(emptyzip, sizeof(emptyzip));
    ms.SaveToFile(zipfile);
    ms.Free;
  end;

  numt := NumProcessThreads;

  shellobj := CreateOleObject('Shell.Application');

  srcfldr := shellobj.NameSpace(sourcefolder);
  destfldr := shellobj.NameSpace(zipfile);

  shellfldritems := srcfldr.Items;

  if (filter <> '') then
    shellfldritems.Filter(SHCONTF_INCLUDEHIDDEN or SHCONTF_NONFOLDERS or SHCONTF_FOLDERS,filter);

  destfldr.CopyHere(shellfldritems, 0);

  // wait till all shell threads are terminated
  while NumProcessThreads <> numt do
  begin
    sleep(100);
  end;
end;

end.