使用Delphi 10 Seattle，我需要获取任何文件的文本内容。
我已经GetFileContentsFromIFilter SPFilter.pas来自http://develop.shorterpath.com/spfree/default.asp，但我无法让它发挥作用：
uses SPFilter;
procedure TForm1.btnTestClick(Sender: TObject);
var
FilterStream: TStringStream;
begin
FilterStream := TStringStream.Create;
try
if SPFilter.GetFileContentsFromIFilter(Trim(edtFile.Text), FilterStream) then // D:\Readme.txt
begin
FilterStream.Seek(0, soFromBeginning);
Memo1.Lines.LoadFromStream(FilterStream);
end;
finally
FilterStream.Free;
end;
end;
这是SPFilter.pas单位：
(******************************************************************************)
(* SPFilter - Read file content using IFilter interface *)
(* Shorter Path Free Components 1.0 *)
(* *)
(* Copyright (c) 2003 Shorter Path Software *)
(* http://develop.shorterpath.com *)
(******************************************************************************)
unit SPFilter;
interface
uses
CodeSiteLogging,
Classes;
function GetFileContentsFromIFilter(const FileName: string; OutData: TStream): Boolean;
implementation
uses
Windows, SysUtils, Registry, ActiveX, Filter;
function GetFileContentsFromIFilter(const FileName: string;
OutData: TStream): Boolean;
var
Reg: TRegistry;
DocType, DocClass, HandlerClass, PersistClass, FilterDLL: string;
DLLHandle: THandle;
ClassFactory: IClassFactory;
FilterObj: IFilter;
PersistFile: IPersistFile;
DllGetClassObject: TDllGetClassObject;
DllCanUnloadNow: TDLLCanUnloadNow;
Res, ChunkRes: HResult;
pFlags: ULONG;
WFileName: WideString;
StatChunk: TStatChunk;
cwcBuffer: ULONG;
awcBuffer: PWideChar;
Txt: WideString;
AnsiTxt: string;
t: string;
EndOfChunksCount: Integer;
begin
Result := False;
{ Find filter DLL }
FilterDLL := EmptyStr;
{ Step 1: Determine the CLSID }
Reg := TRegistry.Create(KEY_READ);
Reg.RootKey := HKEY_LOCAL_MACHINE;
{ A. Locate document type }
DocType := 'Software\Classes\' + ExtractFileExt(FileName);
if Reg.OpenKey(DocType, False) then
begin
DocType := Reg.ReadString(EmptyStr);
Reg.CloseKey;
CodeSite.Send('document type', DocType); // -> txtfile
if Length(DocType) > 0 then
begin
{ B. Locate document class }
if Reg.OpenKey('Software\Classes\' + DocType + '\CLSID', False) then // FALSE HERE!!
begin
CodeSite.Send('CLSID');
DocClass := Reg.ReadString(EmptyStr);
Reg.CloseKey;
end;
end;
{ Step 2: Determine the Persistent Handler }
if Length(DocClass) > 0 then
begin
if Reg.OpenKey('Software\Classes\CLSID\' + DocClass + '\PersistentHandler', False) then
begin
HandlerClass := Reg.ReadString(EmptyStr);
Reg.CloseKey;
end;
end;
{ Step 3: Determine the IFilter Persistent Handler GUID }
if Length(HandlerClass) > 0 then
begin
if Reg.OpenKey('Software\Classes\CLSID\' + HandlerClass +
'\PersistentAddinsRegistered\' + GUIDToString(IID_IFilter), False) then
begin
PersistClass := Reg.ReadString(EmptyStr);
Reg.CloseKey;
end;
end;
{ Step 4: Determine the Filter DLL }
if Length(PersistClass) > 0 then
begin
if Reg.OpenKey('Software\Classes\CLSID\' + PersistClass + '\InprocServer32', False) then
begin
FilterDLL := Reg.ReadString(EmptyStr);
Reg.CloseKey;
end;
end;
end;
Reg.Free;
{ Use Filter DLL to read the file }
if Length(FilterDLL) > 0 then
begin
DLLHandle := LoadLibrary(PChar(FilterDLL));
if DLLHandle <> 0 then
begin
@DllGetClassObject := GetProcAddress(DLLHandle, 'DllGetClassObject');
@DllCanUnloadNow := GetProcAddress(DLLHandle, 'DllCanUnloadNow');
if Assigned(DllGetClassObject) then
begin
{ Get Class Factory }
DllGetClassObject(StringToGUID(PersistClass), IClassFactory, ClassFactory);
if Assigned(ClassFactory) then
begin
{ Get IFilter object }
ClassFactory.CreateInstance(nil, IFilter, FilterObj);
if Assigned(FilterObj) then
begin
FilterObj.QueryInterface(IPersistFile, PersistFile);
if Assigned(PersistFile) then
begin
WFileName := FileName;
PersistFile.Load(PWideChar(WFileName), 0);
EndOfChunksCount := 0;
Res := FilterObj.Init(0, 0, nil, pFlags);
if Res = S_OK then
//if FilterObj.Init(0, 0, nil, pFlags) = S_OK then
begin
repeat
ChunkRes := FilterObj.GetChunk(StatChunk);
if ChunkRes = S_OK then
begin
if (StatChunk.flags and CHUNK_TEXT) <> 0 then
begin
GetMem(awcBuffer, 16384*2);
repeat
cwcBuffer := 16384;
FillChar(awcBuffer^, cwcBuffer, 0);
Res := FilterObj.GetText(cwcBuffer, awcBuffer);
if cwcBuffer > 0 then
begin
SetLength(Txt, cwcBuffer*2);
FillChar(PWideChar(Txt)^, cwcBuffer*2, 0);
Move(awcBuffer^, PWideChar(Txt)^, cwcBuffer*2);
SetLength(AnsiTxt, cwcBuffer*2);
FillChar(PChar(AnsiTxt)^, cwcBuffer*2, 0);
WideCharToMultiByte(CP_ACP, 0, PWideChar(Txt),
cwcBuffer, PAnsiChar(AnsiTxt), cwcBuffer*2, ' ', nil);
SetLength(AnsiTxt, StrLen(PChar(AnsiTxt)));
t := t + AnsiTxt;
end;
until Res = FILTER_E_NO_MORE_TEXT;
FreeMem(awcBuffer);
end;
end;
if ChunkRes = FILTER_E_END_OF_CHUNKS then
Inc(EndOfChunksCount) else
EndOfChunksCount := 0;
until EndOfChunksCount > 1;
{ Return True for success }
Result := True;
end;
end;
{ Release filter }
PersistFile := nil;
FilterObj := nil;
end;
{ Release Class Factory }
ClassFactory := nil;
end;
end;
if Assigned(DllCanUnloadNow) then
begin
if DllCanUnloadNow = S_OK then
FreeLibrary(DLLHandle) else
end else
FreeLibrary(DLLHandle);
end;
end;
{ Write data to stream }
if Result then
try
OutData.Write(t[1], Length(t));
except
Result := False;
end;
end;
end.
从评论中可以看出＆＃34; FALSE HERE＆＃34;它无法获取.TXT文件的CLSID。但是，txtfile注册表项中没有CLSID项。那么这里有什么问题？
有人知道如何获取任何文件的内容吗？