c - 如何更新（刷新）控制台屏幕？

Question

我正在编写一个在屏幕上显示一些信息的程序，我希望它们每秒更新一次。

我应该怎么办？

我正在 Windows 上编写一个 C 控制台应用程序。

Answer 1

钢琴家，您可以使用 WinAPI 函数与控制台一起工作。

HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
if (!hConsole)
    return;

之后确定光标位置：

CONSOLE_SCREEN_BUFFER_INFO csbi = {0};
GetConsoleScreenBufferInfo(hConsole, &csbi);
COORD coordCur = csbi.dwCursorPosition;

和...

while (TRUE) {  // your cycle goes here
    // ...
    // now you can change position of the cursor
    coordCur.X = newX;
    coordCur.Y = newY;
    SetConsoleCursorPosition(hConsole, coordCur);
    // and print any information from the new position
    printf("..."); // old text will be replaced
}

因此，如果您想更改一小段文本，则无需清除和刷新所有控制台。

附言。不要忘记释放句柄：

CloseHandle(hConsole);

Answer 2

Since you are on Windows, you can do this:

system('cls')

Here is an example:

#include <stdio.h>

int main()
{
    printf("Press enter to clear the screen.");
    getchar();
    system("cls");
    return 0;
}

If you are developing using Microsoft Visual Studoo and you want to programmatically clear the screen by outputting spaces, see Example 2 at http://msdn.microsoft.com/en-us/library/windows/desktop/ms682022(v=vs.85).aspx.

Answer 3

If you had searched google before asking, you would have found this link right in the first results.

To quote one of the methods:

Windows:

#include <windows.h>

void ClearScreen()
  {
  HANDLE                     hStdOut;
  CONSOLE_SCREEN_BUFFER_INFO csbi;
  DWORD                      count;
  DWORD                      cellCount;
  COORD                      homeCoords = { 0, 0 };

  hStdOut = GetStdHandle( STD_OUTPUT_HANDLE );
  if (hStdOut == INVALID_HANDLE_VALUE) return;

  /* Get the number of cells in the current buffer */
  if (!GetConsoleScreenBufferInfo( hStdOut, &csbi )) return;
  cellCount = csbi.dwSize.X *csbi.dwSize.Y;

  /* Fill the entire buffer with spaces */
  if (!FillConsoleOutputCharacter(
    hStdOut,
    (TCHAR) ' ',
    cellCount,
    homeCoords,
    &count
    )) return;

  /* Fill the entire buffer with the current colors and attributes */
  if (!FillConsoleOutputAttribute(
    hStdOut,
    csbi.wAttributes,
    cellCount,
    homeCoords,
    &count
    )) return;

  /* Move the cursor home */
  SetConsoleCursorPosition( hStdOut, homeCoords );
  }

Answer 4

有一篇关于该主题的知识库文章。

两种选择：

1. 编写一个以编程方式清除屏幕的函数

   /* Standard error macro for reporting API errors */ 
   #define PERR(bSuccess, api){if(!(bSuccess)) printf("%s:Error %d from %s \ 
       on line %d\n", __FILE__, GetLastError(), api, __LINE__);}
   
   void cls( HANDLE hConsole )
   {
       COORD coordScreen = { 0, 0 };    /* here's where we'll home the
                                           cursor */ 
       BOOL bSuccess;
       DWORD cCharsWritten;
       CONSOLE_SCREEN_BUFFER_INFO csbi; /* to get buffer info */ 
       DWORD dwConSize;                 /* number of character cells in
                                           the current buffer */ 
   
       /* get the number of character cells in the current buffer */ 
   
       bSuccess = GetConsoleScreenBufferInfo( hConsole, &csbi );
       PERR( bSuccess, "GetConsoleScreenBufferInfo" );
       dwConSize = csbi.dwSize.X * csbi.dwSize.Y;
   
       /* fill the entire screen with blanks */ 
   
       bSuccess = FillConsoleOutputCharacter( hConsole, (TCHAR) ' ',
          dwConSize, coordScreen, &cCharsWritten );
       PERR( bSuccess, "FillConsoleOutputCharacter" );
   
       /* get the current text attribute */ 
   
       bSuccess = GetConsoleScreenBufferInfo( hConsole, &csbi );
       PERR( bSuccess, "ConsoleScreenBufferInfo" );
   
       /* now set the buffer's attributes accordingly */ 
   
       bSuccess = FillConsoleOutputAttribute( hConsole, csbi.wAttributes,
          dwConSize, coordScreen, &cCharsWritten );
       PERR( bSuccess, "FillConsoleOutputAttribute" );
   
       /* put the cursor at (0, 0) */ 
   
       bSuccess = SetConsoleCursorPosition( hConsole, coordScreen );
       PERR( bSuccess, "SetConsoleCursorPosition" );
       return;
   }
   

2. 使用系统函数（不是很漂亮；需要启动 shell 和命令）

   system("cls");