How To Performing Clear Screen (CLS) in a Console Application

Some non-Microsoft versions of C++ provide a clrscr function for clearing the screen in a DOS application. However, there is no Win32 Application Programming Interface (API) or C-Runtime function that will perform this function.

To accomplish this task for a Win32 console application, use one of the following methods:

• Use a system function.
• Write a function that will programmatically clear the screen.

These methods are described in the following "More Information" section. Back to the top

Use a system function

#include 

void main()
{
 system("cls");
}
   

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Write a function that will programmatically clear the screen

The following function clears the screen:

 /* 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;
}
   

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APPLIES TO

• Microsoft Win32 Application Programming Interface, when used with:
• Microsoft Windows NT 3.51 Service Pack 5
• Microsoft Windows NT 4.0
• Microsoft Windows 95
• Microsoft Windows 98 Standard Edition
• Microsoft Windows 2000 Standard Edition
• Microsoft Windows Millennium Edition
• the operating system: Microsoft Windows XP

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Keywords:

kbhowto kbapi kbconsole kbkernbase kbcode KB99261

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http://support.microsoft.com/kb/99261