Thread: help w/ReadConsoleOutputCharacter()

I am trying to find a way to read a character that has already been displayed on the screen. I found a function called ReadConsoleOutputCharacter. I am pretty sure this is what I want but I wasn't sure how to use it and I couldn't find any help on google.

Heres the msdn link on that function
http://msdn.microsoft.com/library/de...tcharacter.asp

yes, this is where i found the function but i was confused about what all the parameters should equal and stuff like that

>but i was confused about what all the parameters should equal and stuff like that

Try this.

Code:

   char buf[BUFSIZ];
   COORD coord = {0,0};
   DWORD num_read;

   HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
   if (ReadConsoleOutputCharacter(hConsole, (LPTSTR) buf, (DWORD) BUFSIZ, coord, (LPDWORD) &num_read) == 0)
   {
      cout << "Error reading console." << endl;
      return 1;
   }
   cout << buf;

If you haven't already, check the FAQ for a clear screen function and gotoxy function.

Well, I've never used any of these special Windows Console functions, but I have done some Windows programming, so maybe I can help. (?)

All of these parameter types are structures and typedef's defined in windows.h:
HANDLE
LPTSTR
DWORD
COORD
LPDWORD

DWORD is simply a variable (long integer?), and LP means "long pointer", so LPSTR is a pointer to a c-style string (character array), and LPDWORD is a pointer to a DWORD.

There should be some information on these "types" in your compiler's help file.

You can use your own variable names if you want, but you will have to define and initialize them before calling the function.

Like swoopy shows, GetStdHandle() should be used to initialize hConsoleOutput (or hConsole if you wish to use that name).

I'm not sure about initializing COORD. I assume that X and Y are in pixels. With Windows programs, there is more than one way to reference window coordinates, but I think pixels are the default.