本文是针对 控制台输入输出机制 一文的实例说明。相关理论内容建议参考之。
实例a 控制台高层输入输出接口实例
本实例首先使用控制台默认输入输出模式，调用ReadFile和WriteFile函数，用于说明用于控制台的字符串输入输出；之后修改控制台输入模式，关闭行输入模式和回显输入模式，重复使用ReadFile和WriteFile函数。最后再程序退出时恢复控制台默认的输入输出模式及字符颜色。
代码中使用NewLine函数在行输入模式禁用情况下模拟换行处理，即将控制台屏幕缓冲的光标移动到下一行开始位置。
代码如下：
// 控制台高层输入输出接口实例，HighLevelIoFuncDemo // 1. WriteFile输出字符串，ReadFile读取字符串 // 2. 关闭行输入和回显输入之后的字符输入输出处理 // 3. 手工实现换行及滚屏处理 // 建议使用vs2005以上版本编译 #include <windows.h> void NewLine(void); void ScrollScreenBuffer(HANDLE, INT); HANDLE hStdout, hStdin; CONSOLE_SCREEN_BUFFER_INFO csbiInfo; int main(void) { LPSTR lpszPrompt1 = "Type a line and press Enter, or q to quit: "; LPSTR lpszPrompt2 = "Type any key, or q to quit: "; CHAR chBuffer[256]; DWORD cRead, cWritten, fdwMode, fdwOldMode; WORD wOldColorAttrs; // Get handles to STDIN and STDOUT. hStdin = GetStdHandle(STD_INPUT_HANDLE); hStdout = GetStdHandle(STD_OUTPUT_HANDLE); if (hStdin == INVALID_HANDLE_VALUE || hStdout == INVALID_HANDLE_VALUE) { MessageBox(NULL, TEXT("GetStdHandle"), TEXT("Console Error"), MB_OK); return 1; } // Save the current text colors. if (! GetConsoleScreenBufferInfo(hStdout, &csbiInfo)) { MessageBox(NULL, TEXT("GetConsoleScreenBufferInfo"), TEXT("Console Error"), MB_OK); return 1; } wOldColorAttrs = csbiInfo.wAttributes; // Set the text attributes to draw red text on black background. if (! SetConsoleTextAttribute(hStdout, FOREGROUND_RED | FOREGROUND_INTENSITY)) { MessageBox(NULL, TEXT("SetConsoleTextAttribute"), TEXT("Console Error"), MB_OK); return 1; } // Write to STDOUT and read from STDIN by using the default // modes. Input is echoed automatically, and ReadFile // does not return until a carriage return is typed. // // The default input modes are line, processed, and echo. // The default output modes are processed and wrap at EOL. while (1) { if (! WriteFile( hStdout, // output handle lpszPrompt1, // prompt string lstrlenA(lpszPrompt1), // string length &cWritten, // bytes written NULL) ) // not overlapped { MessageBox(NULL, TEXT("WriteFile"), TEXT("Console Error"), MB_OK); return 1; } if (! ReadFile( hStdin, // input handle chBuffer, // buffer to read into 255, // size of buffer &cRead, // actual bytes read NULL) ) // not overlapped break; if (chBuffer[0] == 'q') break; } // Turn off the line input and echo input modes if (! GetConsoleMode(hStdin, &fdwOldMode)) { MessageBox(NULL, TEXT("GetConsoleMode"), TEXT("Console Error"), MB_OK); return 1; } fdwMode = fdwOldMode & ~(ENABLE_LINE_INPUT | ENABLE_ECHO_INPUT); if (! SetConsoleMode(hStdin, fdwMode)) { MessageBox(NULL, TEXT("SetConsoleMode"), TEXT("Console Error"), MB_OK); return 1; } // ReadFile returns when any input is available. // WriteFile is used to echo input. NewLine(); while (1) { if (! WriteFile( hStdout, // output handle lpszPrompt2, // prompt string lstrlenA(lpszPrompt2), // string length &cWritten, // bytes written NULL) ) // not overlapped { MessageBox(NULL, TEXT("WriteFile"), TEXT("Console Error"), MB_OK); return 1; } if (! ReadFile(hStdin, chBuffer, 1, &cRead, NULL)) break; if (chBuffer[0] == '\r') NewLine(); else if (! WriteFile(hStdout, chBuffer, cRead, &cWritten, NULL)) break; else NewLine(); if (chBuffer[0] == 'q') break; } // Restore the original console mode. SetConsoleMode(hStdin, fdwOldMode); // Restore the original text colors. SetConsoleTextAttribute(hStdout, wOldColorAttrs); return 0; } // The NewLine function handles carriage returns when the processed // input mode is disabled. It gets the current cursor position // and resets it to the first cell of the next row. void NewLine(void) { if (! GetConsoleScreenBufferInfo(hStdout, &csbiInfo)) { MessageBox(NULL, TEXT("GetConsoleScreenBufferInfo"), TEXT("Console Error"), MB_OK); return; } csbiInfo.dwCursorPosition.X = 0; // If it is the last line in the screen buffer, scroll // the buffer up. if ((csbiInfo.dwSize.Y-1) == csbiInfo.dwCursorPosition.Y) { ScrollScreenBuffer(hStdout, 1); } // Otherwise, advance the cursor to the next line. else csbiInfo.dwCursorPosition.Y += 1; if (! SetConsoleCursorPosition(hStdout, csbiInfo.dwCursorPosition)) { MessageBox(NULL, TEXT("SetConsoleCursorPosition"), TEXT("Console Error"), MB_OK); return; } } void ScrollScreenBuffer(HANDLE h, INT x) { SMALL_RECT srctScrollRect, srctClipRect; CHAR_INFO chiFill; COORD coordDest; srctScrollRect.Left = 0; srctScrollRect.Top = 1; srctScrollRect.Right = csbiInfo.dwSize.X - (SHORT)x; srctScrollRect.Bottom = csbiInfo.dwSize.Y - (SHORT)x; // The destination for the scroll rectangle is one row up. coordDest.X = 0; coordDest.Y = 0; // The clipping rectangle is the same as the scrolling rectangle. // The destination row is left unchanged. srctClipRect = srctScrollRect; // Set the fill character and attributes. chiFill.Attributes = FOREGROUND_RED|FOREGROUND_INTENSITY; chiFill.Char.AsciiChar = (char)' '; // Scroll up one line. ScrollConsoleScreenBuffer( h, // screen buffer handle &srctScrollRect, // scrolling rectangle &srctClipRect, // clipping rectangle coordDest, // top left destination cell &chiFill); // fill character and color }