Question

如何让Delphi将字符串传递给CMD进程的输入管道。我能够得到一个错误管道和输出管道正常运行，不幸的是不是输入管道。我正在使用的代码取自管道的在线教程。原始代码中有几个错误在编译时导致问题。它们已被修复，但在尝试传递输入时仍然存在问题。

以下是Form.Create事件中的代码。我还包括WritePipe和ReadPipe方法。 WritePipe不起作用，ReadPipe确实有效。 Pipe方法中的WriteFile和ReadFile都返回一条成功的消息，但只有ReadPipe才能正常工作。

var
    DosApp: String;
    DosSize: Integer;
    Security : TSecurityAttributes;
    start : TStartUpInfo;
    byteswritten: DWord;
    WriteString : ansistring;
  begin
    CommandText.Clear;
    // get COMSPEC variable, this is the path of the command-interpreter
    SetLength(Dosapp, 255);
    DosSize := GetEnvironmentVariable('COMSPEC', @DosApp[1], 255);
    SetLength(Dosapp, DosSize);

  // create pipes
    With Security do
      begin
        nlength := SizeOf(TSecurityAttributes) ;
        binherithandle := true;
        lpsecuritydescriptor := nil;
      end;

    CreatePipe(InputPipeRead, InputPipeWrite, @Security, 0);
    CreatePipe(OutputPipeRead, OutputPipeWrite, @Security, 0);
    CreatePipe(ErrorPipeRead, ErrorPipeWrite, @Security, 0);

    // start command-interpreter
    FillChar(Start,Sizeof(Start),#0) ;

    //start.hStdInput := InputPipeRead;
    start.hStdOutput := OutputPipeWrite;
    start.hStdError :=  ErrorPipeWrite;

    start.dwFlags := STARTF_USESTDHANDLES + STARTF_USESHOWWINDOW;
    start.wShowWindow := SW_Show;//SW_HIDE;
    start.cb := SizeOf(start) ;

    if CreateProcess('', PChar(DosApp), @Security, @Security, true,
               CREATE_NEW_CONSOLE or SYNCHRONIZE, // CREATE_NO_WINDOW,
               nil, nil, start, ProcessInfo) then
      begin
        MyThread := MainUnit.monitor.Create;  // start monitor thread
        MyThread.Priority := tpHigher;
      end;

    Button1.Enabled := true;
    cmdcount := 1;

end;

写管道：

procedure WritePipeOut(OutputPipe: THandle; InString: PWideChar);
// writes Instring to the pipe handle described by OutputPipe
  var
    count : integer;
    byteswritten: DWord;
    outputstring : PAnsiChar;
    TextBuffer: array[1..32767] of AnsiChar;// char;
    TextString: String;
  begin

// most console programs require CR/LF after their input.

    InString := PWideChar(InString + #13#10);

    WriteFile(InputPipeWrite, InString[1], Length(InString), byteswritten, nil);

  end;

读取管道：

function ReadPipeInput(InputPipe: THandle; var BytesRem: Integer): String;
  {
    reads console output from InputPipe.  Returns the input in function
    result.  Returns bytes of remaining information to BytesRem
  }
  var
    TextBuffer: array[1..32767] of AnsiChar;// char;
    TextString: String;
    BytesRead: Cardinal;
    PipeSize: Integer;
  begin
    Result := '';
    PipeSize := length(TextBuffer);
    // check if there is something to read in pipe
    PeekNamedPipe(InputPipe, nil, PipeSize, @BytesRead, @PipeSize, @BytesRem);
    if bytesread > 0 then
      begin
        ReadFile(InputPipe, TextBuffer, pipesize, bytesread, nil);
        // a requirement for Windows OS system components
        OemToChar(@TextBuffer, @TextBuffer);
        TextString := String(TextBuffer);
        SetLength(TextString, BytesRead);
        Result := TextString;
      end;
  end;

进一步说明;这是为了与Java调试器一起使用，它需要分阶段输入，所以我不相信除了直接操作输入到JDB之外还有任何替代方法。

非常感谢任何帮助！

Answer 1

1）您应该将InputPipeRead作为hStdInput传递到CreateProcess：取消注释您的行start.hStdInput := InputPipeRead;

2）WritePipeOut函数有两个错误：它将一个Unicode（UTF-16LE）字符串写入管道，并跳过第一个字符（因为它写入一个以InString [1]开头的内存区域）。而不是WriteFile(InputPipeWrite, InString[1], Length(InString),...你应该写一些像：

var AnsiBuf: AnsiString;
...
  AnsiBuf := String(InString) + #13#10;
  Write(InputPipeWrite, AnsiBuf[1], Length(AnsiBuf), byteswritten, nil);

Delphi中的管道用于命令提示符

1 个答案: