window.event.keycode-获取按下的键盘值
这里只列出了一些较常用的键盘值更加详细的键盘值请访问此人博客：https://www.cnblogs.com/z-sm/p/3597592.html
详细event.keycode值大全
1 keycode 8 = BackSpace BackSpace
2 keycode 9 = Tab Tab
3 keycode 12 = Clear
4 keycode 13 = Enter
5 keycode 16 = Shift_L
6 keycode 17 = Control_L
7 keycode 18 = Alt_L
8 keycode 19 = Pause
9 keycode 20 = Caps_Lock
10 keycode 27 = Escape Escape
11 keycode 32 = space space
12 keycode 33 = Prior
13 keycode 34 = Next
14 keycode 35 = End
15 keycode 36 = Home
16 keycode 37 = Left
17 keycode 38 = Up
18 keycode 39 = Right
19 keycode 40 = Down
20 keycode 41 = Select
21 keycode 42 = Print
22 keycode 43 = Execute
23 keycode 45 = Insert
24 keycode 46 = Delete
25 keycode 47 = Help
26 keycode 48 = 0 equal braceright
27 keycode 49 = 1 exclam onesuperior
28 keycode 50 = 2 quotedbl twosuperior
29 keycode 51 = 3 section threesuperior
30 keycode 52 = 4 dollar
31 keycode 53 = 5 percent
32 keycode 54 = 6 ampersand
33 keycode 55 = 7 slash braceleft
34 keycode 56 = 8 parenleft bracketleft
35 keycode 57 = 9 parenright bracketright
36 keycode 65 = a A
37 keycode 66 = b B
38 keycode 67 = c C
39 keycode 68 = d D
40 keycode 69 = e E EuroSign
41 keycode 70 = f F
43 keycode 71 = g G
44 keycode 72 = h H
45 keycode 73 = i I
46 keycode 74 = j J
47 keycode 75 = k K
48 keycode 76 = l L
49 keycode 77 = m M mu
50 keycode 78 = n N
51 keycode 79 = o O
52 keycode 80 = p P
53 keycode 81 = q Q at
54 keycode 82 = r R
55 keycode 83 = s S
56 keycode 84 = t T
57 keycode 85 = u U
58 keycode 86 = v V
59 keycode 87 = w W
60 keycode 88 = x X
61 keycode 89 = y Y
62 keycode 90 = z Z
80 keycode 112 = F1
81 keycode 113 = F2
82 keycode 114 = F3
83 keycode 115 = F4
86 keycode 116 = F5
87 keycode 117 = F6
88 keycode 118 = F7
89 keycode 119 = F8
90 keycode 120 = F9
91 keycode 121 = F10
92 keycode 122 = F11
93 keycode 123 = F12