DELPHI中如何用管道实时捕获控制台输出

Question

我让DOS执行实时的一行一行显示出来，从网上找了段代码，无奈还是不能实时显示，请教大家了！帮我看看这段代码哪里出错了，先谢谢！procedure TForm1.RunDosInMemo(const DosApp:string;Amemo:TMemo);
const
  ReadBuffer=2400;  //设置ReadBuffer的大小
var
  Security:TSecurityAttributes;
  ReadPipe,WritePipe:THandle;
  start:TStartUpInfo;
  ProcessInfo:TProcessInformation;
  Buffer:PChar;
  BytesRead:DWord;
  Buf:string;
begin
  with Security do
  begin
    nlength:=sizeof(TSecurityAttributes);
    binherithandle:=true;
    lpsecuritydescriptor:=nil;
  end;
  {创建一个命名管道来捕获Console的输出}
  if CreatePipe(ReadPipe,WritePipe,@Security,0) then
  begin
    Buffer:=AllocMem(ReadBuffer+1);
    FillChar(Start,Sizeof(Start),#0);
    {设置Console程序的启动属性}
    with Start do
    begin
      cb:=sizeof(start);
      start.lpReserved:=nil;
      lpDesktop:=nil;
      lpTitle:=nil;
      dwX:=0;
      dwY:=0;
      dwXSize:=0;
      dwYSize:=0;
      dwXCountChars:=0;
      dwYCountChars:=0;
      dwFillAttribute:=0;
      hStdOutput:=WritePipe; //将输出定向到建立的WritePipe上
      hStdInput:=ReadPipe;   //将输入定向到建立的ReadPipe上
      hStdError:=WritePipe;  //将错误输出定向到建立的WritePipe上
      dwFlags:=STARTF_USESTDHANDLES or STARTF_USESHOWWINDOW;
      wshowwindow:=SW_HIDE;  //设置窗口为hide
    end;
    try
      {创建一个子进程，运行Console}
      if CreateProcess(nil,PChar(DosApp),@Security,@Security,true,
        NORMAL_PRIORITY_CLASS,
        nil,nil,start,ProcessInfo)then
      begin
        Application.ProcessMessages;
        {等待进程运行结束}
        WaitForSingleObject(ProcessInfo.hProcess,INFINITE);
        {关闭程序...开始没有关掉它，如果没有输出的话，程序死掉了。}
        closeHandle(WritePipe);
        buf:='';
        {读取Console的输出}
        repeat
          bytesRead:=0;
          ReadFile(ReadPipe,Buffer[0],ReadBuffer,BytesRead,nil);
          Buffer[BytesRead]:=#0;
          OemToAnsi(Buffer,Buffer);
          Buf:=Buf+String(Buffer);
          Application.ProcessMessages;
        until(bytesRead<ReadBuffer);
        //sendDebug(Buf);
        {按照换行符进行切割，并在Memo中显示出来}
        while pos(#10,buf)>0 do
        begin
          AMemo.Lines.Add(Copy(Buf,1,Pos(#10,buf)-1));
          Delete(Buf,1,Pos(#10,buf));
          Application.ProcessMessages;
        end;
      end;
    finally
      FreeMem(Buffer);
      CloseHandle(ProcessInfo.hProcess);
      CloseHandle(ProcessInfo.hThread);
      CloseHandle(ReadPipe);
    end;
  end;
end;procedure TForm1.Button1Click(Sender: TObject);
begin
  RunDosInMemo('ping 192.168.1.1 -t',Amemo);
end;

Answer 1

首先,利用WIN API函数 Createpipe 建立两个管道(Pipe),然后建立利用CreateProcess函数创建一个控制台程序的进程（这里使用的是Win2000的Dos控制台 cmd.exe）,并且在StartUpInfo参数中指定用刚才建立的三个管道替换标准的输入hStdOutput、输出hStdInput以及错误输出设备hStdError。代码如下：procedure TForm1.InitConsole;
var
    Security: TSecurityAttributes;
    start: TStartUpInfo;
begin
    with Security do begin
      nlength := SizeOf(TSecurityAttributes);
      binherithandle := true;
      lpsecuritydescriptor := nil;
    end;    Createpipe(ReadOut, WriteOut, @Security, 0);
    Createpipe(ReadIn, WriteIn, @Security, 0);    with Security do begin
      nlength := SizeOf(TSecurityAttributes);
      binherithandle := true;
      lpsecuritydescriptor := nil;
    end;    FillChar(Start, Sizeof(Start), #0);
    start.cb := SizeOf(start);
    start.hStdOutput := WriteOut;
    start.hStdInput := ReadIn;
    start.hStdError := WriteOut;
    start.dwFlags := STARTF_USESTDHANDLES +
      STARTF_USESHOWWINDOW;
    start.wShowWindow := SW_HIDE;    CreateProcess(nil,
      PChar('cmd'),
      @Security,
      @Security,
      true,
      NORMAL_PRIORITY_CLASS,
      nil,
      nil,
      start,
      ProcessInfo)
end;然后利用一个定时器，从对应输出设备的管道中读取控制台返回的信息，并显示。代码如下：function TForm1.ReadFromPipe(Pipe: THandle): string;
var
    Buffer: PChar;
    BytesRead: DWord;
begin
    Result := '';
    if GetFileSize(Pipe, nil) = 0 then Exit;    Buffer := AllocMem(ReadBuffer + 1);
    repeat
      BytesRead := 0;
      ReadFile(Pipe, Buffer[0],
        ReadBuffer, BytesRead, nil);
      if BytesRead > 0 then begin
        Buffer[BytesRead] := #0;
        OemToAnsi(Buffer, Buffer);
        Result := string(Buffer);
      end;
    until (BytesRead < ReadBuffer);
    FreeMem(Buffer);
end;procedure TForm1.Timer1Timer(Sender: TObject);
var
    s: string;
begin
    s := ReadFromPipe(ReadOut);
    if s <> '' then begin
      Memo1.Lines.Text := Memo1.Lines.Text + s;
      Memo1.SelStart := Length(Memo1.Lines.Text);
      Memo1.SelLength := 0;
    end;
end;在下方的输入框内输入命令之后，则通过向输入设备对应的管道发送命令来实现命令行的输入，代码如下：procedure TForm1.WriteToPipe(Pipe: THandle; Value: string);
var
    len: integer;
    BytesWrite: DWord;
    Buffer: PChar;
begin
    len := Length(Value) + 1;
    Buffer := PChar(Value + #10);
    WriteFile(Pipe, Buffer[0], len, BytesWrite, nil);
end;procedure TForm1.Button1Click(Sender: TObject);
begin
    if Trim(cbCmd.Text) <> '' then begin
      WriteToPipe(WriteIn, cbCmd.Text);
      if cbCMD.ItemIndex > -1 then
        cbCMD.Items.Delete(cbCMD.ItemIndex);
      cbcmd.Items.Insert(0, cbCmd.Text);
      cbCmd.Text:='';
    end;
end;这里要注意的是发送命令行的时候必须添加换行字符#10，才能被Dos控制台接受并执行

Answer 2

procedure RunDosInMemo(Que:String;EnMemo:TMemo);   const 
      CUANTOBUFFER = 2000;
  var 
     Seguridades         : TSecurityAttributes; 
     PaLeer,PaEscribir   : THandle; 
     start               : TStartUpInfo; 
     ProcessInfo         : TProcessInformation; 
     Buffer              : Pchar; 
     BytesRead           : DWord; 
     CuandoSale          : DWord; 
  begin 
    //安全描述 可以省略 
    with Seguridades do 
    begin 
       nlength              := SizeOf(TSecurityAttributes); 
       binherithandle       := true; 
       lpsecuritydescriptor := nil; 
    end; 
  
    {Creamos el pipe...} 
    if Createpipe (PaLeer, PaEscribir, @Seguridades, 0) then 
    begin 
       //申请缓冲 
       Buffer  := AllocMem(CUANTOBUFFER + 1);
    
       //创建STARTUPINFO 
       FillChar(Start,Sizeof(Start),#0);
       start.cb          := SizeOf(start); 
       start.hStdOutput  := PaEscribir; 
       start.hStdInput   := PaLeer; 
       start.dwFlags     := STARTF_USESTDHANDLES + 
                            STARTF_USESHOWWINDOW; 
       start.wShowWindow := SW_HIDE; 
         
       //执行子进程  
      if CreateProcess(nil, 
         PChar(Que), 
         @Seguridades, 
         @Seguridades, 
          true, 
          NORMAL_PRIORITY_CLASS, 
         nil, 
         nil, 
          start, 
          ProcessInfo) 
      then 
        begin 
          {Espera a que termine la ejecucion} 
          repeat 
             //使用信号量技术来避免CPU时间片被抢占
             CuandoSale := WaitForSingleObject( ProcessInfo.hProcess,100);
             Application.ProcessMessages; 
          //until (CuandoSale <> WAIT_TIMEOUT);
          {Leemos la Pipe} 
          //repeat
             BytesRead := 0; 
    
            {Llenamos un troncho de la pipe, igual a nuestro buffer} 
             //执行标准输出 
             ReadFile(PaLeer,Buffer[0],CUANTOBUFFER,BytesRead,nil); 
            {La convertimos en una string terminada en cero}
             Buffer[BytesRead]:= #0;
            {Convertimos caracteres DOS a ANSI}
             OemToAnsi(Buffer,Buffer);
             EnMemo.Lines.Add(String(Buffer));
          until (CuandoSale <> WAIT_TIMEOUT);//(BytesRead < CUANTOBUFFER);
        end; 
       FreeMem(Buffer);
    
       //释放资源 
       CloseHandle(ProcessInfo.hProcess); 
       CloseHandle(ProcessInfo.hThread); 
       CloseHandle(PaLeer);
       CloseHandle(PaEscribir); 
    end; 
  end;

Answer 3

用线程吧,我以前用BCB写过一个,可最近没时间改成D的,程序不多,思路与上面类似.有人改一下或等我有空改.
主程序://---------------------------------------------------------------------------#include <vcl.h>
#pragma hdrstop#include "proc1.h"
#include "proct.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
#define DisplayError ShowMessageTForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------HANDLE hd,hi;
bool run =true;
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   SECURITY_ATTRIBUTES sa;
   HANDLE hOutputReadTmp,hOutputRead,hOutputWrite;
   HANDLE hInputWriteTmp,hInputRead,hInputWrite;
   HANDLE hErrorWrite;
   sa.nLength= sizeof(SECURITY_ATTRIBUTES);
   sa.lpSecurityDescriptor = NULL;
   sa.bInheritHandle = TRUE;
      // Create the child output pipe.
      if (!CreatePipe(&hOutputReadTmp,&hOutputWrite,&sa,0))
         DisplayError("CreatePipe");
      // Create a duplicate of the output write handle for the std error
      // write handle. This is necessary in case the child application
      // closes one of its std output handles.
      if (!DuplicateHandle(GetCurrentProcess(),hOutputWrite,
                           GetCurrentProcess(),&hErrorWrite,0,
                           TRUE,DUPLICATE_SAME_ACCESS))
         DisplayError("DuplicateHandle");
      // Create the child input pipe.
      if (!CreatePipe(&hInputRead,&hInputWriteTmp,&sa,0))
         DisplayError("CreatePipe");
      // Create new output read handle and the input write handles. Set
      // the Properties to FALSE. Otherwise, the child inherits the
      // properties and, as a result, non-closeable handles to the pipes
      // are created.
      if (!DuplicateHandle(GetCurrentProcess(),hOutputReadTmp,
                           GetCurrentProcess(),
                           &hOutputRead, // Address of new handle.
                           0,FALSE, // Make it uninheritable.
                           DUPLICATE_SAME_ACCESS))
         DisplayError("DupliateHandle");      if (!DuplicateHandle(GetCurrentProcess(),hInputWriteTmp,
                           GetCurrentProcess(),
                           &hInputWrite, // Address of new handle.
                           0,FALSE, // Make it uninheritable.
                           DUPLICATE_SAME_ACCESS))
      DisplayError("DupliateHandle");
      // Close inheritable copies of the handles you do not want to be
      // inherited.
      if (!CloseHandle(hOutputReadTmp)) DisplayError("CloseHandle");
      if (!CloseHandle(hInputWriteTmp)) DisplayError("CloseHandle");      PROCESS_INFORMATION pi;
      STARTUPINFO si;      ZeroMemory(&si,sizeof(STARTUPINFO));
      si.cb = sizeof(STARTUPINFO);
      si.dwFlags = STARTF_USESTDHANDLES |  STARTF_USESHOWWINDOW;
      si.hStdOutput = hOutputWrite;
      si.hStdInput  = hInputRead;
      si.hStdError  = hErrorWrite;
      si.wShowWindow = SW_HIDE;      if (!CreateProcess(NULL,"cmd.exe",NULL,NULL,TRUE,
                         CREATE_NEW_CONSOLE,NULL,NULL,&si,&pi))
         DisplayError("CreateProcess");
      if (!CloseHandle(pi.hThread)) DisplayError("CloseHandle");      if (!CloseHandle(hOutputWrite)) DisplayError("CloseHandle");
      if (!CloseHandle(hInputRead )) DisplayError("CloseHandle");
      if (!CloseHandle(hErrorWrite)) DisplayError("CloseHandle");     hi=hInputWrite;
     hd=hOutputRead;
     proct *p;
     p=new proct(false);
     while(run)
       Application->ProcessMessages();      TerminateProcess(pi.hProcess,0);
      delete p;
     if (!CloseHandle(hOutputRead)) DisplayError("CloseHandle");
      if (!CloseHandle(hInputWrite)) DisplayError("CloseHandle");
      CloseHandle(pi.hProcess);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
 DWORD nn=0;
 String m=Edit1->Text;
 m+="\n";
 if(!WriteFile(hi,m.c_str(),m.Length(),&nn,NULL))
       ShowMessage("Write Error"+String(nn));}
//---------------------------------------------------------------------------线程://---------------------------------------------------------------------------#include <vcl.h>
#pragma hdrstop#include "proct.h"
#include "proc1.h"
#pragma package(smart_init)
//---------------------------------------------------------------------------//   Important: Methods and properties of objects in VCL can only be
//   used in a method called using Synchronize, for example:
//
//      Synchronize(UpdateCaption);
//
//   where UpdateCaption could look like:
//
//      void __fastcall proct::UpdateCaption()
//      {
//        Form1->Caption = "Updated in a thread";
//      }
//---------------------------------------------------------------------------__fastcall proct::proct(bool CreateSuspended)
        : TThread(CreateSuspended)
{
}
//---------------------------------------------------------------------------
extern HANDLE hd;
extern bool run;
void __fastcall proct::Execute()
{
        //---- Place thread code here ----
      CHAR lpBuffer[1];
      DWORD nBytesRead;
      char c;
      String x="";
      while(TRUE)
      {
         nBytesRead=0;
         if (!ReadFile(hd,lpBuffer,sizeof(lpBuffer),
                                          &nBytesRead,NULL) || !nBytesRead)
         {
            if (GetLastError() == ERROR_BROKEN_PIPE)
               break; // pipe done - normal exit path.
            else
               ShowMessage("ReadFile"); // Something bad happened.
         }
         c=lpBuffer[0];
         if (c=='\n')
          {
            Form1->Memo1->Lines->Add(x);
             x="";
          }
          else
           {
             x+=c;
             Form1->Memo1->Lines->Strings[Form1->Memo1->Lines->Count-1]=x;
            }
       }
       run=false;
}
//---------------------------------------------------------------------------按button1初始化,按button2执行edit1中的dos命令,在Memo1中显示
只是还没有编写停止和退出,供参考吧