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Delphi 7和Vista/Windows 7通用对话框 - 事件不起作用

delphidelphi-7openfiledialogtopendialog
10
我正在尝试修改Delphi 7 Dialogs.pas以访问更新的Windows 7打开/保存对话框（请参见使用Delphi创建Windows Vista Ready应用程序）。我可以使用建议的修改显示对话框；但是，例如OnFolderChange和OnCanClose等事件不再起作用。 这似乎与将Flags：=OFN_ENABLEHOOK更改为Flags：=0有关。当Flags设置为0时，TOpenDialog.Wndproc被绕过，适当的CDN_xxxxxxx消息不会被捕获。 有人能否建议对D7 Dialogs.pas进行进一步的代码修改，既可以显示更新的公共对话框，又可以保留原始控件的事件功能？ 谢谢...
4个回答
6
您应该使用IFileDialog Interface并调用其Advise()方法，同时提供IFileDialogEvents Interface的实现。Delphi 7 Windows头文件单元不包含必要的声明，因此必须从SDK头文件中复制（并翻译），但除了这些额外的工作之外，从Delphi 7（甚至更早的Delphi版本）调用此方法不应该有任何问题。

编辑：

好吧，既然您没有对答案做出任何反应，我将添加一些更多信息。如何使用接口的C示例可以在这里找到。只要您有必要的导入单元，就很容易将其转换为Delphi代码。

我在Delphi 4中制作了一个简单的示例。为了简单起见，我创建了一个TOpenDialog的派生类（您可能会修改原始类），并直接在其上实现了IFileDialogEvents：

type
  TVistaOpenDialog = class(TOpenDialog, IFileDialogEvents)
  private
    // IFileDialogEvents implementation
    function OnFileOk(const pfd: IFileDialog): HResult; stdcall;
    function OnFolderChanging(const pfd: IFileDialog;
      const psiFolder: IShellItem): HResult; stdcall;
    function OnFolderChange(const pfd: IFileDialog): HResult; stdcall;
    function OnSelectionChange(const pfd: IFileDialog): HResult; stdcall;
    function OnShareViolation(const pfd: IFileDialog;
      const psi: IShellItem; out pResponse: DWORD): HResult; stdcall;
    function OnTypeChange(const pfd: IFileDialog): HResult; stdcall;
    function OnOverwrite(const pfd: IFileDialog; const psi: IShellItem;
      out pResponse: DWORD): HResult; stdcall;
  public
    function Execute: Boolean; override;
  end;

function TVistaOpenDialog.Execute: Boolean;
var
  guid: TGUID;
  Ifd: IFileDialog;
  hr: HRESULT;
  Cookie: Cardinal;
  Isi: IShellItem;
  pWc: PWideChar;
  s: WideString;
begin
  CLSIDFromString(SID_IFileDialog, guid);
  hr := CoCreateInstance(CLSID_FileOpenDialog, nil, CLSCTX_INPROC_SERVER,
    guid, Ifd);
  if Succeeded(hr) then begin
    Ifd.Advise(Self, Cookie);
    // call DisableTaskWindows() etc.
    // see implementation of Application.MessageBox()
    try
      hr := Ifd.Show(Application.Handle);
    finally
      // call EnableTaskWindows() etc.
      // see implementation of Application.MessageBox()
    end;
    Ifd.Unadvise(Cookie);
    if Succeeded(hr) then begin
      hr := Ifd.GetResult(Isi);
      if Succeeded(hr) then begin
        Assert(Isi <> nil);
        // TODO: just for testing, needs to be implemented properly
        if Succeeded(Isi.GetDisplayName(SIGDN_NORMALDISPLAY, pWc))
          and (pWc <> nil)
        then begin
          s := pWc;
          FileName := s;
        end;
      end;
    end;
    Result := Succeeded(hr);
    exit;
  end;
  Result := inherited Execute;
end;

function TVistaOpenDialog.OnFileOk(const pfd: IFileDialog): HResult;
var
  pszName: PWideChar;
  s: WideString;
begin
  if Succeeded(pfd.GetFileName(pszName)) and (pszName <> nil) then begin
    s := pszName;
    if AnsiCompareText(ExtractFileExt(s), '.txt') = 0 then begin
      Result := S_OK;
      exit;
    end;
  end;
  Result := S_FALSE;
end;

function TVistaOpenDialog.OnFolderChange(const pfd: IFileDialog): HResult;
begin
  Result := S_OK;
end;

function TVistaOpenDialog.OnFolderChanging(const pfd: IFileDialog;
  const psiFolder: IShellItem): HResult;
begin
  Result := S_OK;
end;

function TVistaOpenDialog.OnOverwrite(const pfd: IFileDialog;
  const psi: IShellItem; out pResponse: DWORD): HResult;
begin
  Result := S_OK;
end;

function TVistaOpenDialog.OnSelectionChange(
  const pfd: IFileDialog): HResult;
begin
  Result := S_OK;
end;

function TVistaOpenDialog.OnShareViolation(const pfd: IFileDialog;
  const psi: IShellItem; out pResponse: DWORD): HResult;
begin
  Result := S_OK;
end;

function TVistaOpenDialog.OnTypeChange(const pfd: IFileDialog): HResult;
begin
  Result := S_OK;
end;

如果您在Windows 7上运行此程序，它将显示新的对话框，并仅接受扩展名为txt的文件。这是硬编码的，需要通过对话框的OnClose事件来实现。还有很多工作要做，但提供的代码应该足以作为起点。
谢谢。根据您的建议和其他帖子，我一直在拼凑一个组件，它将模拟原始的TOpenDialog和TSaveDialog属性和事件。像您一样，我从TOpenDialog继承，以更快地启动事情。我很快就会发布我的组件代码... - JeffR
4
这里是 Delphi 7 Vista/Win7 对话框组件的框架（和调用它的单元）。我尝试复制了 TOpenDialog 的事件（例如 OnCanClose）。类型定义未包含在组件中，但可以在网络上的某些更新的 ShlObj 和 ActiveX 单元中找到。
我曾经在尝试将旧格式的筛选器字符串转换为文件类型数组时遇到问题（请参见下文）。因此，现在您可以按如下设置 FileTypes 数组。欢迎任何有关筛选器转换问题或其他改进的帮助。
以下是代码：
{Example of using the TWin7FileDialog delphi component to access the
 Vista/Win7 File Dialog AND handle basic events.}

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Win7FileDialog;

type
  TForm1 = class(TForm)
    btnOpenFile: TButton;
    btnSaveFile: TButton;
    procedure btnOpenFileClick(Sender: TObject);
    procedure btnSaveFileClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    procedure DoDialogCanClose(Sender: TObject; var CanClose: Boolean);
    procedure DoDialogFolderChange(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}


{Using the dialog to open a file}
procedure TForm1.btnOpenFileClick(Sender: TObject);
var
  i: integer;
  aOpenDialog: TWin7FileDialog;
  aFileTypesArray: TComdlgFilterSpecArray;
begin
  aOpenDialog:=TWin7FileDialog.Create(Owner);
  aOpenDialog.Title:='My Win 7 Open Dialog';
  aOpenDialog.DialogType:=dtOpen;
  aOpenDialog.OKButtonLabel:='Open';
  aOpenDialog.DefaultExt:='pas';
  aOpenDialog.InitialDir:='c:\program files\borland\delphi7\source';
  aOpenDialog.Options:=[fosPathMustExist, fosFileMustExist];

  //aOpenDialog.Filter := 'Text files (*.txt)|*.TXT|
    Pascal files (*.pas)|*.PAS|All Files (*.*)|*.*';

  // Create an array of file types
  SetLength(aFileTypesArray,3);
  aFileTypesArray[0].pszName:=PWideChar(WideString('Text Files (*.txt)'));
  aFileTypesArray[0].pszSpec:=PWideChar(WideString('*.txt'));
  aFileTypesArray[1].pszName:=PWideChar(WideString('Pascal Files (*.pas)'));
  aFileTypesArray[1].pszSpec:=PWideChar(WideString('*.pas'));
  aFileTypesArray[2].pszName:=PWideChar(WideString('All Files (*.*)'));
  aFileTypesArray[2].pszSpec:=PWideChar(WideString('*.*'));
  aOpenDialog.FilterArray:=aFileTypesArray;

  aOpenDialog.FilterIndex:=1;
  aOpenDialog.OnCanClose:=DoDialogCanClose;
  aOpenDialog.OnFolderChange:=DoDialogFolderChange;
  if aOpenDialog.Execute then
  begin
    showMessage(aOpenDialog.Filename);
  end;

end;

{Example of using the OnCanClose event}
procedure TForm1.DoDialogCanClose(Sender: TObject;
  var CanClose: Boolean);
begin
  if UpperCase(ExtractFilename(TWin7FileDialog(Sender).Filename))=
    'TEMPLATE.SSN' then
    begin
      MessageDlg('The Template.ssn filename is reserved for use by the system.',
     mtInformation, [mbOK], 0);
      CanClose:=False;
    end
    else
      begin
        CanClose:=True;
      end;
end;

{Helper function to get path from ShellItem}
function PathFromShellItem(aShellItem: IShellItem): string;
var
  hr: HRESULT;
  aPath: PWideChar;
begin
  hr:=aShellItem.GetDisplayName(SIGDN_FILESYSPATH,aPath);
  if hr = 0 then
    begin
      Result:=aPath;
    end
    else
      Result:='';
end;

{Example of handling a folder change}
procedure TForm1.DoDialogFolderChange(Sender: TObject);
var
  aShellItem: IShellItem;
  hr: HRESULT;
  aFilename: PWideChar;
begin
  hr:=TWin7FileDialog(Sender).FileDialog.GetFolder(aShellItem);
  if hr = 0 then
  begin
    // showmessage(PathFromShellItem(aShellItem));
  end;
end;

{Using the dialog to save a file}
procedure TForm1.btnSaveFileClick(Sender: TObject);
var
  aSaveDialog: TWin7FileDialog;
  aFileTypesArray: TComdlgFilterSpecArray;
begin
  aSaveDialog:=TWin7FileDialog.Create(Owner);
  aSaveDialog.Title:='My Win 7 Save Dialog';
  aSaveDialog.DialogType:=dtSave;
  aSaveDialog.OKButtonLabel:='Save';
  aSaveDialog.DefaultExt:='pas';
  aSaveDialog.InitialDir:='c:\program files\borland\delphi7\source';
  aSaveDialog.Options:=[fosNoReadOnlyReturn, fosOverwritePrompt];

  //aSaveDialog.Filter := 'Text files (*.txt)|*.TXT|
    Pascal files (*.pas)|*.PAS';

  {Create an array of file types}
  SetLength(aFileTypesArray,3);
  aFileTypesArray[0].pszName:=PWideChar(WideString('Text Files (*.txt)'));
  aFileTypesArray[0].pszSpec:=PWideChar(WideString('*.txt'));
  aFileTypesArray[1].pszName:=PWideChar(WideString('Pascal Files (*.pas)'));
  aFileTypesArray[1].pszSpec:=PWideChar(WideString('*.pas'));
  aFileTypesArray[2].pszName:=PWideChar(WideString('All Files (*.*)'));
  aFileTypesArray[2].pszSpec:=PWideChar(WideString('*.*'));
  aSaveDialog.FilterArray:=aFileTypesArray;

  aSaveDialog.OnCanClose:=DoDialogCanClose;
  aSaveDialog.OnFolderChange:=DoDialogFolderChange;
  if aSaveDialog.Execute then
  begin
    showMessage(aSaveDialog.Filename);
  end;


end;

end.


{A sample delphi 7 component to access the
 Vista/Win7 File Dialog AND handle basic events.}

unit Win7FileDialog;

interface

uses
  SysUtils, Classes, Forms, Dialogs, Windows,DesignIntf, ShlObj,
  ActiveX, CommDlg;

  {Search the internet for new ShlObj and ActiveX units to get necessary
   type declarations for IFileDialog, etc..  These interfaces can otherwise
   be embedded into this component.}


Type
  TOpenOption = (fosOverwritePrompt,
  fosStrictFileTypes,
  fosNoChangeDir,
  fosPickFolders,
  fosForceFileSystem,
  fosAllNonStorageItems,
  fosNoValidate,
  fosAllowMultiSelect,
  fosPathMustExist,
  fosFileMustExist,
  fosCreatePrompt,
  fosShareAware,
  fosNoReadOnlyReturn,
  fosNoTestFileCreate,
  fosHideMRUPlaces,
  fosHidePinnedPlaces,
  fosNoDereferenceLinks,
  fosDontAddToRecent,
  fosForceShowHidden,
  fosDefaultNoMiniMode,
  fosForcePreviewPaneOn);

  TOpenOptions = set of TOpenOption;

type
  TDialogType = (dtOpen,dtSave);

type
  TWin7FileDialog = class(TOpenDialog)
  private
    { Private declarations }
    FOptions: TOpenOptions;
    FDialogType: TDialogType;
    FOKButtonLabel: string;
    FFilterArray: TComdlgFilterSpecArray;
    procedure SetOKButtonLabel(const Value: string);
  protected
    { Protected declarations }
    function CanClose(Filename:TFilename): Boolean;
    function DoExecute: Bool;
  public
    { Public declarations }
    FileDialog: IFileDialog;
    FileDialogCustomize: IFileDialogCustomize;
    FileDialogEvents: IFileDialogEvents;
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    function Execute: Boolean; override;

  published
    { Published declarations }
    property DefaultExt;
    property DialogType: TDialogType read FDialogType write FDialogType
      default dtOpen;
    property FileName;
    property Filter;
    property FilterArray: TComdlgFilterSpecArray read fFilterArray
      write fFilterArray;
    property FilterIndex;
    property InitialDir;
    property Options: TOpenOptions read FOptions write FOptions
      default [fosNoReadOnlyReturn, fosOverwritePrompt];
    property Title;
    property OKButtonLabel: string read fOKButtonLabel write SetOKButtonLabel;
    property OnCanClose;
    property OnFolderChange;
    property OnSelectionChange;
    property OnTypeChange;
    property OnClose;
    property OnShow;
//    property OnIncludeItem;
  end;

  TFileDialogEvent = class(TInterfacedObject, IFileDialogEvents,
    IFileDialogControlEvents)
  private
    { Private declarations }
    // IFileDialogEvents
    function OnFileOk(const pfd: IFileDialog): HResult; stdcall;
    function OnFolderChanging(const pfd: IFileDialog;
      const psiFolder: IShellItem): HResult; stdcall;
    function OnFolderChange(const pfd: IFileDialog): HResult; stdcall;
    function OnSelectionChange(const pfd: IFileDialog): HResult; stdcall;
    function OnShareViolation(const pfd: IFileDialog; const psi: IShellItem;
      out pResponse: DWORD): HResult; stdcall;
    function OnTypeChange(const pfd: IFileDialog): HResult; stdcall;
    function OnOverwrite(const pfd: IFileDialog; const psi: IShellItem;
      out pResponse: DWORD): HResult; stdcall;
    // IFileDialogControlEvents
    function OnItemSelected(const pfdc: IFileDialogCustomize; dwIDCtl,
      dwIDItem: DWORD): HResult; stdcall;
    function OnButtonClicked(const pfdc: IFileDialogCustomize;
      dwIDCtl: DWORD): HResult; stdcall;
    function OnCheckButtonToggled(const pfdc: IFileDialogCustomize;
      dwIDCtl: DWORD; bChecked: BOOL): HResult; stdcall;
    function OnControlActivating(const pfdc: IFileDialogCustomize;
      dwIDCtl: DWORD): HResult; stdcall;
  public
    { Public declarations }
    ParentDialog: TWin7FileDialog;

end;

procedure Register;

implementation

constructor TWin7FileDialog.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
end;

destructor TWin7FileDialog.Destroy;
begin
  inherited Destroy;
end;

procedure TWin7FileDialog.SetOKButtonLabel(const Value: string);
begin
  if Value<>fOKButtonLabel then
    begin
      fOKButtonLabel := Value;
    end;
end;

function TWin7FileDialog.CanClose(Filename: TFilename): Boolean;
begin
  Result := DoCanClose;
end;

{Helper function to get path from ShellItem}
function PathFromShellItem(aShellItem: IShellItem): string;
var
  hr: HRESULT;
  aPath: PWideChar;
begin
  hr:=aShellItem.GetDisplayName(SIGDN_FILESYSPATH,aPath);
  if hr = 0 then
    begin
      Result:=aPath;
    end
    else
      Result:='';
end;

function TFileDialogEvent.OnFileOk(const pfd: IFileDialog): HResult; stdcall
var
  aShellItem: IShellItem;
  hr: HRESULT;
  aFilename: PWideChar;
begin
  {Get selected filename and check CanClose}
  aShellItem:=nil;
  hr:=pfd.GetResult(aShellItem);
  if hr = 0 then
    begin
      hr:=aShellItem.GetDisplayName(SIGDN_FILESYSPATH,aFilename);
      if hr = 0 then
        begin
          ParentDialog.Filename:=aFilename;
          if not ParentDialog.CanClose(aFilename) then
          begin
            result := s_FALSE;
            Exit;
          end;
        end;
    end;

  result := s_OK;
end;

function TFileDialogEvent.OnFolderChanging(const pfd: IFileDialog;
  const psiFolder: IShellItem): HResult; stdcall
begin
  {Not currently handled}
  result := s_OK;
end;

function TFileDialogEvent.OnFolderChange(const pfd: IFileDialog):
  HResult; stdcall
begin
  ParentDialog.DoFolderChange;
  result := s_OK;
end;

function TFileDialogEvent.OnSelectionChange(const pfd: IFileDialog):
  HResult; stdcall
begin
  ParentDialog.DoSelectionChange;
  result := s_OK;
end;

function TFileDialogEvent.OnShareViolation(const pfd: IFileDialog;
  const psi: IShellItem;out pResponse: DWORD): HResult; stdcall
begin
  {Not currently handled}
  result := s_OK;
end;

function TFileDialogEvent.OnTypeChange(const pfd: IFileDialog):
  HResult; stdcall;
begin
  ParentDialog.DoTypeChange;
  result := s_OK;
end;

function TFileDialogEvent.OnOverwrite(const pfd: IFileDialog;
  const psi: IShellItem;out pResponse: DWORD): HResult; stdcall;
begin
  {Not currently handled}
  result := s_OK;
end;

function TFileDialogEvent.OnItemSelected(const pfdc: IFileDialogCustomize;
  dwIDCtl,dwIDItem: DWORD): HResult; stdcall;
begin
  {Not currently handled}
//  Form1.Caption := Format('%d:%d', [dwIDCtl, dwIDItem]);
  result := s_OK;
end;

function TFileDialogEvent.OnButtonClicked(const pfdc: IFileDialogCustomize;
  dwIDCtl: DWORD): HResult; stdcall;
begin
  {Not currently handled}
  result := s_OK;
end;

function TFileDialogEvent.OnCheckButtonToggled(const pfdc: IFileDialogCustomize;
  dwIDCtl: DWORD; bChecked: BOOL): HResult; stdcall;
begin
  {Not currently handled}
  result := s_OK;
end;

function TFileDialogEvent.OnControlActivating(const pfdc: IFileDialogCustomize;
  dwIDCtl: DWORD): HResult; stdcall;
begin
  {Not currently handled}
  result := s_OK;
end;

procedure ParseDelimited(const sl : TStrings; const value : string;
  const delimiter : string) ;
var
   dx : integer;
   ns : string;
   txt : string;
   delta : integer;
begin
   delta := Length(delimiter) ;
   txt := value + delimiter;
   sl.BeginUpdate;
   sl.Clear;
   try
     while Length(txt) > 0 do
     begin
       dx := Pos(delimiter, txt) ;
       ns := Copy(txt,0,dx-1) ;
       sl.Add(ns) ;
       txt := Copy(txt,dx+delta,MaxInt) ;
     end;
   finally
     sl.EndUpdate;
   end;
end;


//function TWin7FileDialog.DoExecute(Func: Pointer): Bool;
function TWin7FileDialog.DoExecute: Bool;
var
  aFileDialogEvent: TFileDialogEvent;
  aCookie: cardinal;
  aWideString: WideString;
  aFilename: PWideChar;
  hr: HRESULT;
  aShellItem: IShellItem;
  aShellItemFilter: IShellItemFilter;
  aComdlgFilterSpec: TComdlgFilterSpec;
  aComdlgFilterSpecArray: TComdlgFilterSpecArray;
  i: integer;
  aStringList: TStringList;
  aFileTypesCount: integer;
  aFileTypesArray: TComdlgFilterSpecArray;
  aOptionsSet: Cardinal;

begin
  if DialogType = dtSave then
  begin
    CoCreateInstance(CLSID_FileSaveDialog, nil, CLSCTX_INPROC_SERVER,
      IFileSaveDialog, FileDialog);
  end
  else
  begin
    CoCreateInstance(CLSID_FileOpenDialog, nil, CLSCTX_INPROC_SERVER,
      IFileOpenDialog, FileDialog);
  end;

//  FileDialog.QueryInterface(
//    StringToGUID('{8016B7B3-3D49-4504-A0AA-2A37494E606F}'),
//    FileDialogCustomize);
//  FileDialogCustomize.AddText(1000, 'My first Test');

  {Set Initial Directory}
  aWideString:=InitialDir;
  aShellItem:=nil;
  hr:=SHCreateItemFromParsingName(PWideChar(aWideString), nil,
    StringToGUID(SID_IShellItem), aShellItem);
  FileDialog.SetFolder(aShellItem);

  {Set Title}
  aWideString:=Title;
  FileDialog.SetTitle(PWideChar(aWideString));

  {Set Options}
  aOptionsSet:=0;
  if fosOverwritePrompt in Options then aOptionsSet:=
    aOptionsSet + FOS_OVERWRITEPROMPT;
  if fosStrictFileTypes in Options then aOptionsSet:=
    aOptionsSet + FOS_STRICTFILETYPES;
  if fosNoChangeDir in Options then aOptionsSet:=
    aOptionsSet + FOS_NOCHANGEDIR;
  if fosPickFolders in Options then aOptionsSet:=
    aOptionsSet + FOS_PICKFOLDERS;
  if fosForceFileSystem in Options then aOptionsSet:=
    aOptionsSet + FOS_FORCEFILESYSTEM;
  if fosAllNonStorageItems in Options then aOptionsSet:=
    aOptionsSet + FOS_ALLNONSTORAGEITEMS;
  if fosNoValidate in Options then aOptionsSet:=
    aOptionsSet + FOS_NOVALIDATE;
  if fosAllowMultiSelect in Options then aOptionsSet:=
    aOptionsSet + FOS_ALLOWMULTISELECT;
  if fosPathMustExist in Options then aOptionsSet:=
    aOptionsSet + FOS_PATHMUSTEXIST;
  if fosFileMustExist in Options then aOptionsSet:=
     aOptionsSet + FOS_FILEMUSTEXIST;
  if fosCreatePrompt in Options then aOptionsSet:=
    aOptionsSet + FOS_CREATEPROMPT;
  if fosShareAware in Options then aOptionsSet:=
    aOptionsSet + FOS_SHAREAWARE;
  if fosNoReadOnlyReturn in Options then aOptionsSet:=
    aOptionsSet + FOS_NOREADONLYRETURN;
  if fosNoTestFileCreate in Options then aOptionsSet:=
    aOptionsSet + FOS_NOTESTFILECREATE;
  if fosHideMRUPlaces in Options then aOptionsSet:=
    aOptionsSet + FOS_HIDEMRUPLACES;
  if fosHidePinnedPlaces in Options then aOptionsSet:=
    aOptionsSet + FOS_HIDEPINNEDPLACES;
  if fosNoDereferenceLinks in Options then aOptionsSet:=
    aOptionsSet + FOS_NODEREFERENCELINKS;
  if fosDontAddToRecent in Options then aOptionsSet:=
    aOptionsSet + FOS_DONTADDTORECENT;
  if fosForceShowHidden in Options then aOptionsSet:=
    aOptionsSet + FOS_FORCESHOWHIDDEN;
  if fosDefaultNoMiniMode in Options then aOptionsSet:=
    aOptionsSet + FOS_DEFAULTNOMINIMODE;
  if fosForcePreviewPaneOn in Options then aOptionsSet:=
    aOptionsSet + FOS_FORCEPREVIEWPANEON;
  FileDialog.SetOptions(aOptionsSet);

  {Set OKButtonLabel}
  aWideString:=OKButtonLabel;
  FileDialog.SetOkButtonLabel(PWideChar(aWideString));

  {Set Default Extension}
  aWideString:=DefaultExt;
  FileDialog.SetDefaultExtension(PWideChar(aWideString));

  {Set Default Filename}
  aWideString:=FileName;
  FileDialog.SetFilename(PWideChar(aWideString));

  {Note: Attempting below to automatically parse an old style filter string into
   the newer FileType array; however the below code overwrites memory when the
   stringlist item is typecast to PWideChar and assigned to an element of the
   FileTypes array.  What's the correct way to do this??}

  {Set FileTypes (either from Filter or FilterArray)}
  if length(Filter)>0 then
  begin
  {
  aStringList:=TStringList.Create;
  try
    ParseDelimited(aStringList,Filter,'|');
    aFileTypesCount:=Trunc(aStringList.Count/2)-1;
    i:=0;
    While i <= aStringList.Count-1 do
    begin
      SetLength(aFileTypesArray,Length(aFileTypesArray)+1);
      aFileTypesArray[Length(aFileTypesArray)-1].pszName:=
        PWideChar(WideString(aStringList[i]));
      aFileTypesArray[Length(aFileTypesArray)-1].pszSpec:=
        PWideChar(WideString(aStringList[i+1]));
      Inc(i,2);
    end;
    FileDialog.SetFileTypes(length(aFileTypesArray),aFileTypesArray);
  finally
    aStringList.Free;
  end;
  }
  end
  else
  begin
    FileDialog.SetFileTypes(length(FilterArray),FilterArray);
  end;


  {Set FileType (filter) index}
  FileDialog.SetFileTypeIndex(FilterIndex);

  aFileDialogEvent:=TFileDialogEvent.Create;
  aFileDialogEvent.ParentDialog:=self;
  aFileDialogEvent.QueryInterface(IFileDialogEvents,FileDialogEvents);
  FileDialog.Advise(aFileDialogEvent,aCookie);

  hr:=FileDialog.Show(Application.Handle);
  if hr = 0 then
    begin
      aShellItem:=nil;
      hr:=FileDialog.GetResult(aShellItem);
      if hr = 0 then
        begin
          hr:=aShellItem.GetDisplayName(SIGDN_FILESYSPATH,aFilename);
          if hr = 0 then
            begin
              Filename:=aFilename;
            end;
        end;
      Result:=true;
    end
    else
    begin
      Result:=false;
    end;

  FileDialog.Unadvise(aCookie);
end;

function TWin7FileDialog.Execute: Boolean;
begin
  Result := DoExecute;
end;


procedure Register;
begin
  RegisterComponents('Dialogs', [TWin7FileDialog]);
end;

end.
顺便提一下，我在定义过滤器时也遇到了问题，除非像你上面那样硬编码一个接一个地写入代码中，否则就无法使用旧格式。我通过在为pszName和pszSpec赋值时使用StringToOleStr来解决这个问题：<!-- language: lang-js -->aFileTypesArray[Ind].pszName := StringToOleStr(FilterList[Idx]); - FileVoyager
请忽略 "<!-- language: lang-js -->" 的提醒。复制粘贴和编辑超时了 ;( - FileVoyager
你的示例在 Delphi 6 中无法编译。Win7FileDialog 单元是什么？CLSID_FileOpenDialog 也找不到。 - Paul
2

JeffR - 你的过滤代码问题与将转换为WideString的内容强制转换为PWideChar有关。转换后的WideString未被分配给任何变量，因此可能在堆栈上或堆上，保存指向堆栈或堆上临时值的指针本质上是危险的！

如loursonwinny所建议的，您可以使用StringToOleStr，但这样做会导致内存泄漏，因为包含创建的OleStr的内存永远不会被释放。

我重新修改了代码的这一部分：

{Set FileTypes (either from Filter or FilterArray)}
  if length(Filter)>0 then
  begin
    aStringList:=TStringList.Create;
    try
      ParseDelimited(aStringList,Filter,'|');
      i:=0;
      While i <= aStringList.Count-1 do
      begin
        SetLength(aFileTypesArray,Length(aFileTypesArray)+1);
        aFileTypesArray[Length(aFileTypesArray)-1].pszName:=
          StringToOleStr(aStringList[i]);
        aFileTypesArray[Length(aFileTypesArray)-1].pszSpec:=
          StringToOleStr(aStringList[i+1]);
        Inc(i,2);
      end;
      FileDialog.SetFileTypes(length(aFileTypesArray),aFileTypesArray);
    finally
      for i := 0 to Length(aFileTypesArray) - 1 do
      begin
        SysFreeString(aFileTypesArray[i].pszName);
        SysFreeString(aFileTypesArray[i].pszSpec);
      end;
      aStringList.Free;
    end;
  end
  else
  begin
    FileDialog.SetFileTypes(length(FilterArray),FilterArray);
  end;

非常感谢你提供的代码示例，它为我节省了很多工作！
0
我稍微查了一下，为FPC/Lazarus做了这个快速补丁，但当然你也可以将其作为D7升级的基础：

（已删除，请使用当前的FPC源代码，因为此功能已应用了错误修复）

注意：未经测试，可能包含D7中不存在的符号。

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