js method to obtain and determine keyboard keys_javascript skills
The example in this article describes the method of obtaining and judging keyboard keys in js. Share it with everyone for your reference, the details are as follows:
Keyboard events in js are often used, so I collected the key codes corresponding to keyboard events to share:
keyCode 8 = BackSpace BackSpace keyCode 9 = Tab Tab keyCode 12 = Clear keyCode 13 = Enter keyCode 16 = Shift_L keyCode 17 = Control_L keyCode 18 = Alt_L keyCode 19 = Pause keyCode 20 = Caps_Lock keyCode 27 = Escape Escape keyCode 32 = space keyCode 33 = Prior keyCode 34 = Next keyCode 35 = End keyCode 36 = Home keyCode 37 = Left keyCode 38 = Up keyCode 39 = Right keyCode 40 = Down keyCode 41 = Select keyCode 42 = Print keyCode 43 = Execute keyCode 45 = Insert keyCode 46 = Delete keyCode 47 = Help keyCode 48 = 0 equal braceright keyCode 49 = 1 exclam onesuperior keyCode 50 = 2 quotedbl twosuperior keyCode 51 = 3 section threesuperior keyCode 52 = 4 dollar keyCode 53 = 5 percent keyCode 54 = 6 ampersand keyCode 55 = 7 slash braceleft keyCode 56 = 8 parenleft bracketleft keyCode 57 = 9 parenright bracketright keyCode 65 = a A keyCode 66 = b B keyCode 67 = c C keyCode 68 = d D keyCode 69 = e E EuroSign keyCode 70 = f F keyCode 71 = g G keyCode 72 = h H keyCode 73 = i I keyCode 74 = j J keyCode 75 = k K keyCode 76 = l L keyCode 77 = m M mu keyCode 78 = n N keyCode 79 = o O keyCode 80 = p P keyCode 81 = q Q at keyCode 82 = r R keyCode 83 = s S keyCode 84 = t T keyCode 85 = u U keyCode 86 = v V keyCode 87 = w W keyCode 88 = x X keyCode 89 = y Y keyCode 90 = z Z keyCode 96 = KP_0 KP_0 keyCode 97 = KP_1 KP_1 keyCode 98 = KP_2 KP_2 keyCode 99 = KP_3 KP_3 keyCode 100 = KP_4 KP_4 keyCode 101 = KP_5 KP_5 keyCode 102 = KP_6 KP_6 keyCode 103 = KP_7 KP_7 keyCode 104 = KP_8 KP_8 keyCode 105 = KP_9 KP_9 keyCode 106 = KP_Multiply KP_Multiply keyCode 107 = KP_Add KP_Add keyCode 108 = KP_Separator KP_Separator keyCode 109 = KP_Subtract KP_Subtract keyCode 110 = KP_Decimal KP_Decimal keyCode 111 = KP_Divide KP_Divide keyCode 112 = F1 keyCode 113 = F2 keyCode 114 = F3 keyCode 115 = F4 keyCode 116 = F5 keyCode 117 = F6 keyCode 118 = F7 keyCode 119 = F8 keyCode 120 = F9 keyCode 121 = F10 keyCode 122 = F11 keyCode 123 = F12 keyCode 124 = F13 keyCode 125 = F14 keyCode 126 = F15 keyCode 127 = F16 keyCode 128 = F17 keyCode 129 = F18 keyCode 130 = F19 keyCode 131 = F20 keyCode 132 = F21 keyCode 133 = F22 keyCode 134 = F23 keyCode 135 = F24 keyCode 136 = Num_Lock keyCode 137 = Scroll_Lock keyCode 187 = acute grave keyCode 188 = comma semicolon keyCode 189 = minus underscore keyCode 190 = period colon keyCode 192 = numbersign apostrophe keyCode 210 = plusminus hyphen macron keyCode 211 = keyCode 212 = copyright registered keyCode 213 = guillemotleft guillemotright keyCode 214 = masculine ordfeminine keyCode 215 = ae AE keyCode 216 = cent yen keyCode 217 = questiondown exclamdown keyCode 218 = onequarter onehalf threequarters keyCode 220 = less greater bar keyCode 221 = plus asterisk asciitilde keyCode 227 = multiply division keyCode 228 = acircumflex Acircumflex keyCode 229 = ecircumflex Ecircumflex keyCode 230 = icircumflex Icircumflex keyCode 231 = ocircumflex Ocircumflex keyCode 232 = ucircumflex Ucircumflex keyCode 233 = ntilde Ntilde keyCode 234 = yacute Yacute keyCode 235 = oslash Ooblique keyCode 236 = aring Aring keyCode 237 = ccedilla Ccedilla keyCode 238 = thorn THORN keyCode 239 = eth ETH keyCode 240 = diaeresis cedilla currency keyCode 241 = agrave Agrave atilde Atilde keyCode 242 = egrave Egrave keyCode 243 = igrave Igrave keyCode 244 = ograve Ograve otilde Otilde keyCode 245 = ugrave Ugrave keyCode 246 = adiaeresis Adiaeresis keyCode 247 = ediaeresis Ediaeresis keyCode 248 = idiaeresis Idiaeresis keyCode 249 = odiaeresis Odiaeresis keyCode 250 = udiaeresis Udiaeresis keyCode 251 = ssharp question backslash keyCode 252 = asciicircum degree keyCode 253 = 3 sterling keyCode 254 = Mode_switch
Use the keyCode attribute of the event object to determine the input key value
eg:
Key-value correspondence table
A 0X65 U 0X85 B 0X66 V 0X86 C 0X67 W 0X87 D 0X68 X 0X88 E 0X69 Y 0X89 F 0X70 Z 0X90 G 0X71 0 0X48 H 0X72 1 0X49 I 0X73 2 0X50 J 0X74 3 0X51 K 0X75 4 0X52 L 0X76 5 0X53 M 0X77 6 0X54 N 0X78 7 0X55 O 0X79 8 0X56 P 0X80 9 0X57 Q 0X81 ESC 0X1B R 0X82 CTRL 0X11 S 0X83 SHIFT 0X10 T 0X84 ENTER 0XD
If you want to use key combinations, you can determine whether these keys are pressed at the same time. For example, the combination of the ctrl key, shift key, and alt key can determine whether the ctrl key, shift key, and alt key are pressed multiple times.
js gets keyboard events:
<script type="text/javascript" language=JavaScript charset="UTF-8"> document.onkeydown=function(event){ var e = event || window.event || arguments.callee.caller.arguments[0]; if(e && e.keyCode==27){ // 按 Esc //要做的事情 } if(e && e.keyCode==113){ // 按 F2 //要做的事情 } if(e && e.keyCode==13){ // enter 键 //要做的事情 } }; </script>
As long as you define the actions of these keys, they will respond when you press these keys in the browser. It is compatible with all current browsers.
JS to determine keyboard keys
window.document.onkeydown = disableRefresh; function disableRefresh(evt){ evt = (evt) ? evt : window.event if (evt.keyCode) { if(evt.keyCode == 116){ //do something } } }
The key code is the same as the example above.
Use the keyCode attribute of the event object to determine the input key value
eg:
if(event.keyCode==13){ var ieKey=event.keyCode;//获得键值,数字形式的 var realkey=String.fromCharCode(ieKey) //将数字形式的键值转化为真实的按键 alert(realkey); }
The key-value correspondence table is the same as the example above
I hope this article will be helpful to everyone in JavaScript programming.

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