文件分割成一個TFileStream的

Question

我做兩個功能的加入，在TFileStream的劃分文件，代碼：

加入

procedure TFormHome.btnJoinClick(Sender: TObject); 
var 
    InStream, OutStream: TFileStream; 
    OutFileName, InFileName1, InFileName2: string; 
begin 
    OutFileName := 'salida.out'; 
    InFileName1 := 'image.jpg'; 
    InFileName2 := 'test.exe'; 
    OutStream := TFileStream.Create(OutFileName, fmCreate); 
    try 
    InStream := TFileStream.Create(InFileName1, fmOpenRead); 
    ShowMessage(IntToStr(InStream.Size)); 
    try 
     OutStream.CopyFrom(InStream, InStream.Size); 
    finally 
     InStream.Free; 
    end; 
    InStream := TFileStream.Create(InFileName2, fmOpenRead); 
    ShowMessage(IntToStr(InStream.Size)); 
    try 
     OutStream.CopyFrom(InStream, InStream.Size); 
    finally 
     InStream.Free; 
    end; 
    finally 
    OutStream.Free; 
    end; 
end; 

鴻溝

procedure TFormHome.btnUnJoinClick(Sender: TObject); 
var 
    Source, Target: TStream; 
    Buffer: array of Byte; 
    i: Integer; 
    SourceName, TargetNames: string; 
    SizeTargets: Integer; 
begin 
    SourceName := 'salida.out'; 
    TargetNames := 'test.exe'; 
    SizeTargets := 2232832; 
    Source := TFileStream.Create(SourceName, fmOpenRead); 
    Target := TFileStream.Create(TargetNames, fmCreate); 
    try 
    SetLength(Buffer, SizeTargets); 
    Source.ReadBuffer(Pointer(Buffer)^, Length(Buffer)); 
    Target.WriteBuffer(Buffer[0], Length(Buffer)); 
    finally 
    Target.Free; 
    end; 
end; 

的問題是，當我劃分文件時，可執行文件中斷並運行時，我想顯示如下錯誤：

Windows can not find the file "route ..." Make sure the name is spelled correctly and try again 

或

The version of this file is not compatible with the version of Windows you are running ... (and then talking about 32 or 64 bits) 

檢查與所述可執行的第二功能的大小是好的。

的問題是，在第二個代碼，結果都在文件被破壞

我該如何解決這個問題？

Answer 1

您正在將多個輸入文件連接在一起，而不在輸出中指示一個文件結束且下一個開始。您的分隔代碼不知道哪些字節屬於JPG，哪些字節屬於EXE。

例如，您顯示的分隔代碼是提取JPG字節並將其保存到.exe文件。所以當然.exe文件不會正確運行。

爲了提取EXE，您必須先提取/跳過JPG，這意味着您必須知道JPG中有多少個字節。所以，你需要輸入文件大小存儲所加入的輸出，而不僅僅是他們的數據，例如：

procedure TFormHome.btnJoinClick(Sender: TObject); 
var 
    OutStream: TFileStream; 

    procedure AddFile(const FileName: sstring); 
    var 
    InStream: TStream; 
    Size: Int64; 
    begin 
    InStream := TFileStream.Create(FileName, fmOpenRead or fmShareDenyWrite); 
    try 
     Size := InStream.Size; 
     OutStream.WriteBuffer(Size, SizeOf(Size)); 
     OutStream.CopyFrom(InStream, Size); 
    finally 
     InStream.Free; 
    end; 
    end; 

begin 
    OutStream := TFileStream.Create('salida.out', fmCreate); 
    try 
    AddFile('image.jpg'); 
    AddFile('test.exe'); 
    finally 
    OutStream.Free; 
    end; 
end; 

procedure TFormHome.btnUnJoinClick(Sender: TObject); 
var 
    Source: TStream; 

    procedure SkipFile; 
    var 
    Size: Int64; 
    begin 
    Source.ReadBuffer(Size, SizeOf(Size)); 
    Source.Seek(Size, soCurrent); 
    end; 

    procedure ExtractFile(const FileName: string); 
    var 
    Target: TStream; 
    Size: Int64; 
    begin 
    Source.ReadBuffer(Size, SizeOf(Size)); 

    Target := TFileStream.Create(FileName, fmCreate); 
    try 
     Target.CopyFrom(Source, Size); 
    finally 
     Target.Free; 
    end; 
    end; 

begin 
    Source := TFileStream.Create('salida.out', fmOpenRead or fmShareDenyWrite); 
    try 
    SkipFile; 
    ExtractFile('test.exe'); 
    finally 
    Source.Free; 
    end; 
end; 

我建議你考慮將文件名以及：

procedure TFormHome.btnJoinClick(Sender: TObject); 
var 
    OutStream: TFileStream; 

    procedure AddFile(const FileName: string); 
    var 
    InStream: TStream; 
    Name: UTF8String; 
    Len: Integer; 
    FileSize, TotalSize: Int64; 
    begin 
    InStream := TFileStream.Create(FileName, fmOpenRead or fmShareDenyWrite); 
    try 
     Name := UTF8String(ExtractFileName(FileName)); 
     Len := Length(Name); 

     FileSize := InStream.Size; 

     TotalSize := SizeOf(Len) + Len + SizeOf(FileSize) + FileSize; 
     OutStream.WriteBuffer(TotalSize, SizeOf(TotalSize)); 

     OutStream.WriteBuffer(Len, SizeOf(Len)); 
     OutStream.WriteBuffer(PAnsiChar(Name)^, Len); 
     OutStream.WriteBuffer(FileSize, SizeOf(FileSize)); 
     OutStream.CopyFrom(InStream, FileSize); 
    finally 
     InStream.Free; 
    end; 
    end; 

begin 
    OutStream := TFileStream.Create('salida.out', fmCreate); 
    try 
    AddFile('image.jpg'); 
    AddFile('test.exe'); 
    finally 
    OutStream.Free; 
    end; 
end; 

procedure TFormHome.btnUnJoinClick(Sender: TObject); 
var 
    Source: TStream; 

    procedure SkipFile; 
    var 
    TotalSize: Int64; 
    begin 
    Source.ReadBuffer(TotalSize, SizeOf(TotalSize)); 
    Source.Seek(TotalSize, soCurrent); 
    end; 

    procedure ExtractFile; 
    var 
    Target: TStream; 
    TotalSize, FileSize: Int64; 
    Name: UTF8String; 
    Len: Integer; 
    Pos: Int64; 
    begin 
    Source.ReadBuffer(TotalSize, SizeOf(TotalSize)); 
    Pos := Source.Position; 

    Source.ReadBuffer(Len, SizeOf(Len)); 
    SetLength(Name, Len); 
    Source.ReadBuffer(PAnsiChar(Name)^, Len); 

    Source.ReadBuffer(FileSize, SizeOf(FileSize)); 

    Target := TFileStream.Create(String(Name), fmCreate); 
    try 
     Target.CopyFrom(Source, FileSize); 
    finally 
     Target.Free; 
    end; 

    if (Source.Position - Pos) <> TotalSize then 
     raise Exception.Create('Extract failed. Bad position'); 
    end; 

begin 
    Source := TFileStream.Create('salida.out', fmOpenRead or fmShareDenyWrite); 
    try 
    SkipFile; 
    ExtractFile; 
    finally 
    Source.Free; 
    end; 
end;