要實現一個屏幕鍵盤
是系統范圍的鉤子
什麼是鉤子(Hook)
鉤子(Hook)是Windows提供的一種消息處理機制平台
鉤子的作用范圍
一共有兩種范圍(類型)的鉤子
Hook 類型
Windows共有
(
WH_KEYBOARD_LL Hook監視輸入到線程消息隊列中的鍵盤消息
(
WH_MOUSE_LL Hook監視輸入到線程消息隊列中的鼠標消息
下面的 class 把 API 調用封裝起來以便調用
IntPtr lParam);
安裝鉤子
使用SetWindowsHookEx函數(API函數)
對於某些類型的Hook
使用完鉤子後
將這個文件編譯成一個dll
但是
API函數提供虛擬鍵盤代碼的調用即可模擬鍵盤輸入
把他們連接起來就是一次按鍵過程
自己實現一個 KeyBoardButton 控件用作按鈕
在這些 Button 的 Click 事件裡面模擬一個按鍵過程
其中 combinationVKButtonsMap 是一個 IDictionary
標准鍵盤上的每一個鍵都有虛擬鍵碼( VK_CODE)與之對應。還有一些其他的常量,
把它寫在一個靜態 class 裡吧。
1 // KeyboardConstaint.cs
2 internal static class KeyboardConstaint {
3 internal static readonly short VK_F1 = 0x70;
4 internal static readonly short VK_F2 = 0x71;
5 internal static readonly short VK_F3 = 0x72;
6 internal static readonly short VK_F4 = 0x73;
7 internal static readonly short VK_F5 = 0x74;
8 internal static readonly short VK_F6 = 0x75;
9 internal static readonly short VK_F7 = 0x76;
10 internal static readonly short VK_F8 = 0x77;
11 internal static readonly short VK_F9 = 0x78;
12 internal static readonly short VK_F10 = 0x79;
13 internal static readonly short VK_F11 = 0x7A;
14 internal static readonly short VK_F12 = 0x7B;
15
16 internal static readonly short VK_LEFT = 0x25;
17 internal static readonly short VK_UP = 0x26;
18 internal static readonly short VK_RIGHT = 0x27;
19 internal static readonly short VK_DOWN = 0x28;
20
21 internal static readonly short VK_NONE = 0x00;
22 internal static readonly short VK_ESCAPE = 0x1B;
23 internal static readonly short VK_EXECUTE = 0x2B;
24 internal static readonly short VK_CANCEL = 0x03;
25 internal static readonly short VK_RETURN = 0x0D;
26 internal static readonly short VK_ACCEPT = 0x1E;
27 internal static readonly short VK_BACK = 0x08;
28 internal static readonly short VK_TAB = 0x09;
29 internal static readonly short VK_DELETE = 0x2E;
30 internal static readonly short VK_CAPITAL = 0x14;
31 internal static readonly short VK_NUMLOCK = 0x90;
32 internal static readonly short VK_SPACE = 0x20;
33 internal static readonly short VK_DECIMAL = 0x6E;
34 internal static readonly short VK_SUBTRACT = 0x6D;
35
36 internal static readonly short VK_ADD = 0x6B;
37 internal static readonly short VK_DIVIDE = 0x6F;
38 internal static readonly short VK_MULTIPLY = 0x6A;
39 internal static readonly short VK_INSERT = 0x2D;
40
41 internal static readonly short VK_OEM_1 = 0xBA; // ';:' for US
42 internal static readonly short VK_OEM_PLUS = 0xBB; // '+' any country
43
44 internal static readonly short VK_OEM_MINUS = 0xBD; // '-' any country
45
46 internal static readonly short VK_OEM_2 = 0xBF; // '/?' for US
47 internal static readonly short VK_OEM_3 = 0xC0; // '`~' for US
48 internal static readonly short VK_OEM_4 = 0xDB; // '[{' for US
49 internal static readonly short VK_OEM_5 = 0xDC; // '\|' for US
50 internal static readonly short VK_OEM_6 = 0xDD; // ']}' for US
51 internal static readonly short VK_OEM_7 = 0xDE; // ''"' for US
52 internal static readonly short VK_OEM_PERIOD = 0xBE; // '.>' any country
53 internal static readonly short VK_OEM_COMMA = 0xBC; // ',<' any country
54 internal static readonly short VK_SHIFT = 0x10;
55 internal static readonly short VK_CONTROL = 0x11;
56 internal static readonly short VK_MENU = 0x12;
57 internal static readonly short VK_LWIN = 0x5B;
58 internal static readonly short VK_RWIN = 0x5C;
59 internal static readonly short VK_APPS = 0x5D;
60
61 internal static readonly short VK_LSHIFT = 0xA0;
62 internal static readonly short VK_RSHIFT = 0xA1;
63 internal static readonly short VK_LCONTROL = 0xA2;
64 internal static readonly short VK_RCONTROL = 0xA3;
65 internal static readonly short VK_LMENU = 0xA4;
66 internal static readonly short VK_RMENU = 0xA5;
67
68 internal static readonly short VK_SNAPSHOT = 0x2C;
69 internal static readonly short VK_SCROLL = 0x91;
70 internal static readonly short VK_PAUSE = 0x13;
71 internal static readonly short VK_HOME = 0x24;
72
73 internal static readonly short VK_NEXT = 0x22;
74 internal static readonly short VK_PRIOR = 0x21;
75 internal static readonly short VK_END = 0x23;
76
77 internal static readonly short VK_NUMPAD0 = 0x60;
78 internal static readonly short VK_NUMPAD1 = 0x61;
79 internal static readonly short VK_NUMPAD2 = 0x62;
80 internal static readonly short VK_NUMPAD3 = 0x63;
81 internal static readonly short VK_NUMPAD4 = 0x64;
82 internal static readonly short VK_NUMPAD5 = 0x65;
83 internal static readonly short VK_NUMPAD5NOTHING = 0x0C;
84 internal static readonly short VK_NUMPAD6 = 0x66;
85 internal static readonly short VK_NUMPAD7 = 0x67;
86 internal static readonly short VK_NUMPAD8 = 0x68;
87 internal static readonly short VK_NUMPAD9 = 0x69;
88
89 internal static readonly short KEYEVENTF_EXTENDEDKEY = 0x0001;
90 internal static readonly short KEYEVENTF_KEYUP = 0x0002;
91
92 internal static readonly int GWL_EXSTYLE = -20;
93 internal static readonly int WS_DISABLED = 0X8000000;
94 internal static readonly int WM_SETFOCUS = 0X0007;
95 }
屏幕鍵盤必須是一個不能獲得輸入焦點的窗體,在這個窗體的構造函數裡,可以安裝
一個全局鼠標鉤子,再通過調用 SetWindowLong API 函數完成。
1UserActivityHook hook = new UserActivityHook(true, true);
2hook.MouseActivity += HookOnMouseActivity;
3
4private void HookOnMouseActivity(object sener, HookEx.MouseExEventArgs e) {
5 Point location = e.Location;
6
7 if (e.Button == MouseButtons.Left) {
8 Rectangle captionRect = new Rectangle(this.Location, new Size(this.Width,
9 SystemInformation.CaptionHeight));
10 if (captionRect.Contains(location)) {
11 NativeMethods.SetWindowLong(this.Handle, KeyboardConstaint.GWL_EXSTYLE,
12 (int)NativeMethods.GetWindowLong(this.Handle, KeyboardConstaint.GWL_EXSTYLE)
13 & (~KeyboardConstaint.WS_DISABLED));
14 NativeMethods.SendMessage(this.Handle, KeyboardConstaint.WM_SETFOCUS, IntPtr.Zero,
IntPtr.Zero);
15 } else {
16 NativeMethods.SetWindowLong(this.Handle, KeyboardConstaint.GWL_EXSTYLE,
17 (int)NativeMethods.GetWindowLong(this.Handle, KeyboardConstaint.GWL_EXSTYLE) |
18 KeyboardConstaint.WS_DISABLED);
19 }
20 }
21}
鼠標單擊標題欄,讓屏幕鍵盤可以接收焦點,並激活,單擊其他部分則不激活窗體(如果激活了,其他程序必然取消激活,輸入就無法進行了),這樣才可以進行輸入,並且保證了可以拖動窗體到其他位置。
至此,一個屏幕鍵盤程序差不多完成了,能夠實現與實際鍵盤完全同步。至於窗體,按鍵重繪,以及 Num Lock, Caps Lock,Scroll Lock 等鍵盤燈的模擬,這裡就不講了,如果有興趣,可以下載完整的代碼。
說明:本程序參考了 Jeffrey Richter 先生的著作 CLR via C#, Second Edition, MSDN 以及一些網絡資料。
這是微軟技術的一貫特點,使用簡單。但是如果要深入的話,還是要投入不少精力的
From:http://tw.wingwit.com/Article/program/net/201311/12492.html