做完棋盘之后却无法完成左键点击棋盘，而切换棋盘BMP图片

做完棋盘之后却无法完成左键点击棋盘，而切换棋盘BMP图片

解决办法：

目前推测可能是因为HDC的原因造成无法切换，HDC只能在WM_PAINT消息中使用，其它消息中使用都不会被执行。

有了原因就想出对策，把需要HDC的函数全部放在WM_PAINT消息中去处理，这样就可以共用WM_PAINT中的HDC了

代码：

1. HINSTANCE g_hInst = NULL;
2. HANDLE g_hStdout = NULL; //控制台
3. CHAR szText[256] = { 0 }; //调试用
4. #define PrintLog(x) WriteConsole(g_hStdout, x, strlen(x), 0, 0);
6. int i = 1;
8. //获得坐标
9. int xPos = 0;
10. int yPos = 0;
12. void DrawBk(HDC hDC)
13. {
14. int marc = 0; //控制棋盘所在位置
16. for (int i = 0; i < 10; i++) //画九格横线
17. {
18. MoveToEx(hDC, marc + 50, marc + 50 + i * 48, NULL);
19. LineTo(hDC, marc + 480, marc + 50 + i * 48);
20. }
21. for (int j = 0; j < 10; j++) //画九格直线
22. {
23. MoveToEx(hDC, marc + 50 + j * 48, marc + 50, NULL);
24. LineTo(hDC, marc + 50 + j * 48, marc + 480);
25. }
27. //背景图处理
28. HBITMAP hBitMap = LoadBitmap(g_hInst, MAKEINTRESOURCE(IDB_BKMP1));
29. HDC hBmap = CreateCompatibleDC(hDC);
30. HGDIOBJ hOldBmp = SelectObject(hBmap, hBitMap);
32. //绘图开始
33. for (int i = 0; i < 9; i++)
34. {
35. for (int j = 0; j < 9; j++)
36. {
37. BitBlt(hDC, 50 + j * 48, 50 + i * 48, 48, 48, hBmap, 0, 0, MERGECOPY);
38. }
39. }
42. SelectObject(hDC, hOldBmp);
43. DeleteDC(hBmap);
44. DeleteObject(hBitMap);
45. }
47. void OnLButton(HDC hDC)
48. {
49. //PAINTSTRUCT ps = { 0 };
50. //HDC hDC = BeginPaint(hWnd, &ps);
51. int marc = 0; //控制棋盘所在位置
53. if (xPos>50 && yPos >50)
54. {
55. //背景图处理
56. HBITMAP hBitMap = LoadBitmap(g_hInst, MAKEINTRESOURCE(IDB_BKMP2));
57. HDC hBmap = CreateCompatibleDC(hDC);
58. HGDIOBJ hOldBmp = SelectObject(hBmap, hBitMap);
60. //绘图开始
61. int xPoint = (xPos - 50) / 48;
62. int yPoint = (yPos - 50) / 48;
63. sprintf_s(szText, 256, "OnLButton,x=%d,y=%d\n", xPoint, yPoint);
64. PrintLog(szText);
65. BitBlt(hDC, 50 + xPoint * 48, 50 + yPoint * 48, 48, 48, hBmap, 0, 0, SRCCOPY);
67. SelectObject(hDC, hOldBmp);
68. DeleteDC(hBmap);
69. DeleteObject(hBitMap);
70. }
71. }
73. //OnPaint
74. void OnPaint(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam)
75. {
76. PAINTSTRUCT ps = { 0 };
77. HDC hDC = BeginPaint(hWnd, &ps);
80. if (i == 1) //暂时屏蔽棋盘每次刷新的办法，后面可以用控件解决
81. {
82. DrawBk(hDC);
83. i = 2;
84. }
86. OnLButton(hDC);
88. EndPaint(hWnd, &ps);
89. }

来自为知笔记(Wiz)

转载于:https://www.cnblogs.com/nfking/p/5573147.html