Delphi 中检查文件是否打开

function IsFileInUse(fName: string) : boolean;

var

  HFileRes: HFILE;

begin

  Result := False;

  if not FileExists(fName) then begin

    Exit;

  end;

  HFileRes := CreateFile(PChar(fName)

    ,GENERIC_READ or GENERIC_WRITE

    ,0

    ,nil

    ,OPEN_EXISTING

    ,FILE_ATTRIBUTE_NORMAL

    ,0);

  Result := (HFileRes = INVALID_HANDLE_VALUE);

  if not(Result) then begin

    CloseHandle(HFileRes);

  end;

end;

function IsOpen(const txt:TextFile):Boolean;

const

  fmTextOpenRead = 55217;

  fmTextOpenWrite = 55218;

begin

  Result := (TTextRec(txt).Mode = fmTextOpenRead) or (TTextRec(txt).Mode = fmTextOpenWrite)

end;