Zip erstellen über Shell API

[sx2008]

Zitat von paperboy:

Denn dann setzt
destfldr := shellobj.NameSpace(zipfile); destfldr auf $00000000.

Genau das ist das Problem.
Die Funktion NameSpace() akzeptiert als Argument nur ein Variant.
WideStrings oder Strings führen zu dem Fehler, dass zwar ein Ergebnis vom Typ varDispatch zurückgeliefert wird, aber der Zeiger = nil ist.
Leichte Schlamperei von Microsoft!

Hier die überarbeitete Unit.
Wichtig ist übrigens, dass die Zipdatei mit absolutem Pfad angegeben wird.

Delphi-Quellcode:

unit ShellZipTool;

interface


type
  TShellZip = class(TObject)
  private
    FFilter: string;
    FZipfile: WideString;
    shellobj: Olevariant;

    procedure CreateEmptyZip;
    function GetNameSpaceObj(x:OleVariant):OleVariant;
    function GetNameSpaceObj_zipfile:OleVariant;

  public
     procedure ZipFolder(const sourcefolder:WideString);
     procedure Unzip(const targetfolder: WideString);

     property Zipfile:WideString read FZipfile write FZipfile;
     property Filter:string read FFilter write FFilter;
  end;

function NumProcessThreads: integer;



implementation

uses Classes, Comobj, Windows, Tlhelp32, SysUtils, Variants;

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


function IsValidDispatch(const v:OleVariant):Boolean;
begin
  result := (VarType(v)=varDispatch) and Assigned(TVarData(v).VDispatch);
end;


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

  proch := GetCurrentProcessID;

  hSnapShot := CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);

  Te32.dwSize := sizeof(TTHREADENTRY32);

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

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



{ TShellZip }

procedure TShellZip.CreateEmptyZip;
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;
begin
  // create a new empty ZIP file
  ms := TMemoryStream.Create;
  try
    ms.WriteBuffer(emptyzip, sizeof(emptyzip));
    ms.SaveToFile(Zipfile);
  finally
    ms.Free;
  end;
end;

function TShellZip.GetNameSpaceObj(x:OleVariant): OleVariant;
begin
  // WARNING:
  // the argument of .NameSpace must be a OleVariant
  // don't change "x" to string or WideString
  Result := shellobj.NameSpace(x);
end;

function TShellZip.GetNameSpaceObj_zipfile: OleVariant;
begin
  Result := GetNameSpaceObj(Zipfile);
  if not IsValidDispatch(Result) then
     raise EInvalidOperation.CreateFmt('<%s> invalid zipfile', [zipfile]);
end;


procedure TShellZip.ZipFolder(const sourcefolder: WideString);
var
  srcfldr, destfldr: OleVariant;
  shellfldritems: Olevariant;
  numt: integer;
begin
  if not FileExists(zipfile) then
  begin
    CreateEmptyZip;
  end;

  numt := NumProcessThreads;

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

  srcfldr := GetNameSpaceObj(sourcefolder);
  if not IsValidDispatch(srcfldr) then
     raise EInvalidOperation.CreateFmt('<%s> invalid source', [sourcefolder]);

  destfldr := GetNameSpaceObj_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;


procedure TShellZip.Unzip(const targetfolder: WideString);
var
  srcfldr, destfldr: Olevariant;
  shellfldritems: Olevariant;
begin
  shellobj := CreateOleObject('Shell.Application');

  srcfldr := GetNameSpaceObj_zipfile;

  destfldr := GetNameSpaceObj(targetfolder);
  if not IsValidDispatch(destfldr) then
     raise EInvalidOperation.CreateFmt('<%s> invalid target folder', [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;

end.