6.5.1 一些关于插入符号的函数
|
函数 |
说明 |
|
CreateCaret |
创建和窗口关联的插入符号 |
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SetCaretPos |
设置窗口内的插入符号的位置 |
|
ShowCaret |
显示插入符号 |
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HideCaret |
隐藏插入符号 |
|
DestroyCaret |
销毁插入符号 |
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GetCaretPos |
当前插入符号的位置 |
|
GetCaretBlinkTime |
获得和设置插入符号闪烁时间的函数 |
|
SetCaretBlinkTime |
（1）创建和销毁Caret
|
消息 |
函数 |
备注 |
|
WM_SETFOCUS |
创建Caret |
不在WM_CREATE创建、WM_DESTROY中销毁的原因是一个消息队列仅支持一个Caret，多个窗口必须共享一个Caret。在窗口有焦点时创建，失去焦点时销毁。 |
|
WM_KISSFOCUS |
销毁Caret |
（2）显示和隐藏Caret：
A、创建后默认是隐藏的，要调用ShowCaret显示出来。
B、在非WM_PAINT消息中：要绘制某些东西前必须HideCaret，绘制结束再ShowCaret。
C、HideCaret是叠加的，Hide几次就要Show几次才能使插入符号可见。
6.5.2 TYPER程序
/*------------------------------------------------------------ TYPER.C -- Typeing Program (c) Charles Petzold, 1998 ------------------------------------------------------------*/ #include <windows.h> #define BUFFER(x,y) *(pBuffer+y*cxBuffer+x) LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM); int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) { static TCHAR szAppName[] = TEXT("Typer"); HWND hwnd; MSG msg; WNDCLASS wndclass; wndclass.style = CS_HREDRAW | CS_VREDRAW; wndclass.lpfnWndProc = WndProc; wndclass.cbClsExtra = 0; wndclass.cbWndExtra = 0; wndclass.hInstance = hInstance; wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION); wndclass.hCursor = LoadCursor(NULL, IDC_ARROW); wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); wndclass.lpszMenuName = NULL; wndclass.lpszClassName = szAppName; if (!RegisterClass(&wndclass)) { MessageBox(NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR); return 0; } hwnd = CreateWindow(szAppName, // window class name TEXT("Typing Program"), // window caption WS_OVERLAPPEDWINDOW, // window style CW_USEDEFAULT, // initial x position CW_USEDEFAULT, // initial y position CW_USEDEFAULT, // initial x size CW_USEDEFAULT, // initial y size NULL, // parent window handle NULL, // window menu handle hInstance, // program instance handle NULL); // creation parameters ShowWindow(hwnd, iCmdShow); UpdateWindow(hwnd); while (GetMessage(&msg, NULL, 0, 0)) { TranslateMessage(&msg); DispatchMessage(&msg); } return msg.wParam; } LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) { HDC hdc; PAINTSTRUCT ps; TEXTMETRIC tm; static DWORD dwCharSet = DEFAULT_CHARSET; static int cxChar, cyChar, cxClient, cyClient, cxBuffer, cyBuffer; static int xCaret, yCaret; static TCHAR* pBuffer = NULL; switch (message) { case WM_INPUTLANGCHANGE: dwCharSet = wParam; //继续执行下去 case WM_CREATE: hdc = GetDC(hwnd); SelectObject(hdc, CreateFont(0, 0, 0, 0, 0, 0, 0, 0, dwCharSet, 0, 0, 0, FIXED_PITCH, 0)); GetTextMetrics(hdc, &tm); cxChar = tm.tmAveCharWidth; cyChar = tm.tmHeight; DeleteObject(SelectObject(hdc, GetStockObject(SYSTEM_FONT))); ReleaseDC(hwnd, hdc); //继续执行下去 case WM_SIZE: if (message == WM_SIZE) { cxClient = LOWORD(lParam); cyClient = HIWORD(lParam); } //以字符尺寸为单位，计算窗口大小 cxBuffer = max(1, cxClient / cxChar); cyBuffer = max(1, cyClient / cyChar); //分配字符数组内存大小 if (pBuffer != NULL) free(pBuffer); pBuffer = (TCHAR*)malloc(cxBuffer*cyBuffer*sizeof(TCHAR*)); for (int y = 0; y < cyBuffer; y++) for (int x = 0; x < cxBuffer; x++) BUFFER(x, y) = ' '; //初始化pBuffer为一个‘ ’空字符 //将光标置入左上角 xCaret = 0; yCaret = 0; if (hwnd == GetFocus()) { SetCaretPos(xCaret*cxChar, yCaret*cyChar); } //重绘 InvalidateRect(hwnd, NULL, TRUE); return 0; case WM_SETFOCUS: CreateCaret(hwnd, NULL, 2, cyChar); SetCaretPos(xCaret*cxChar, yCaret*cyChar); ShowCaret(hwnd); return 0; case WM_KILLFOCUS: HideCaret(hwnd); DestroyCaret(); return 0; case WM_KEYDOWN: switch (wParam) { case VK_HOME: xCaret = 0; break; case VK_END: xCaret = cxBuffer - 1; break; case VK_PRIOR: yCaret = 0; break; case VK_NEXT: yCaret = cyBuffer - 1; break; case VK_RIGHT: xCaret = min(xCaret + 1, cxBuffer - 1); break; case VK_LEFT: xCaret = max(0, xCaret - 1); break; case VK_UP: yCaret = max(0, yCaret - 1); break; case VK_DOWN: yCaret = min(yCaret + 1, cyBuffer - 1); break; case VK_DELETE: //注意VK_BACK键当字符消息去处理，这里只处理VK_DELETE //将该行从当前位置后面字符依次前移一格 for (int x = xCaret; x < cxBuffer - 1; x++) { BUFFER(x, yCaret) = BUFFER(x + 1, yCaret); } BUFFER(cxBuffer - 1, yCaret) = ' ';//该行最后一个设为空字符。 HideCaret(hwnd); hdc = GetDC(hwnd); SelectObject(hdc, CreateFont(0, 0, 0, 0, 0, 0, 0, 0, dwCharSet, 0, 0, 0, FIXED_PITCH, 0)); TextOut(hdc, xCaret * cxChar, yCaret * cyChar, &BUFFER(xCaret, yCaret), cyBuffer - xCaret); //重新输出该行xCaret后面的文字 DeleteObject(SelectObject(hdc, GetStockObject(SYSTEM_FONT))); ReleaseDC(hwnd, hdc); ShowCaret(hwnd); break; } SetCaretPos(xCaret*cxChar, yCaret*cyChar); return 0; case WM_CHAR: switch (wParam) { case '': //退格键 if (xCaret>0) { xCaret--; SendMessage(hwnd, WM_KEYDOWN, VK_DELETE, 1); //1为repeat字段的值 } break; case ' ': //Tab键，8个字符长度 do { SendMessage(hwnd, WM_CHAR, ' ', 1); } while (xCaret % 8 != 0); break; case ' ': //换行符，改变y到下一行，x坐标没变。 if (++yCaret == cyBuffer) { yCaret = 0; } break; case ' ': //回车键 xCaret = 0; if (++yCaret == cyBuffer) { yCaret = 0; } break; case 'x1B': //ESC键，清空屏幕 xhh表示1到2位十六进制所代表的任意字符 for (int x = 0; x < cxBuffer; x++) for (int y = 0; y < cyBuffer; y++) BUFFER(x, y) = ' '; xCaret = 0; yCaret = 0; InvalidateRect(hwnd, NULL, TRUE); break; default: BUFFER(xCaret, yCaret) = (TCHAR)wParam; HideCaret(hwnd); hdc = GetDC(hwnd); SelectObject(hdc, CreateFont(0, 0, 0, 0, 0, 0, 0, 0, dwCharSet, 0, 0, 0, FIXED_PITCH, 0)); TextOut(hdc, xCaret * cxChar, yCaret * cyChar, &BUFFER(xCaret, yCaret), 1); DeleteObject(SelectObject(hdc, GetStockObject(SYSTEM_FONT))); ReleaseDC(hwnd, hdc); ShowCaret(hwnd); if (++xCaret == cxBuffer) //插入符号后移 { xCaret = 0; if (++yCaret == cyBuffer) { yCaret = 0; } } break; } SetCaretPos(xCaret*cxChar, yCaret*cyChar); return 0; case WM_PAINT: hdc = BeginPaint(hwnd, &ps); SelectObject(hdc, CreateFont(0, 0, 0, 0, 0, 0, 0, 0, dwCharSet, 0, 0, 0, FIXED_PITCH, 0)); for (int y = 0; y < cyBuffer; y++) TextOut(hdc, 0, y*cyChar, &BUFFER(0, y), cxBuffer); DeleteObject(SelectObject(hdc, GetStockObject(SYSTEM_FONT))); EndPaint(hwnd, &ps); return 0; case WM_DESTROY: if (pBuffer != NULL) free(pBuffer); PostQuitMessage(0); return 0; } return DefWindowProc(hwnd, message, wParam, lParam); }