js获取按键的值

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> 
<HTML> 
<HEAD><TITLE>js 按键记录</TITLE> 
<META NAME="Generator" CONTENT="EditPlus"> 
<META NAME="Author" CONTENT="羽殇仁"> 
<META NAME="Keywords" CONTENT="js 按键记录"> 
<META NAME="Description" CONTENT="js 按键记录"> 
</HEAD> 
<BODY> 
<script type="text/javascript"> 
var keystring = "";//记录按键的字符串 
function $(s){return document.getElementById(s)?document.getElementById(s):s;} 
function keypress(e) 
{ 
var currKey=0,CapsLock=0,e=e||event; 
currKey=e.keyCode||e.which||e.charCode; 
CapsLock=currKey>=65&&currKey<=90; 
switch(currKey) 
{ 
//屏蔽了退格、制表、回车、空格、方向键、删除键 
case 8: case 9:case 13:case 32:case 37:case 38:case 39:case 40:case 46:keyName = "";break; 
default:keyName = String.fromCharCode(currKey); break; 
} 
keystring += keyName; 
} 
function keydown(e) 
{ 
var e=e||event; 
var currKey=e.keyCode||e.which||e.charCode; 
if((currKey>7&&currKey<14)||(currKey>31&&currKey<47)) 
{ 
switch(currKey) 
{ 
case 8: keyName = "[退格]"; break; 
case 9: keyName = "[制表]"; break; 
case 13:keyName = "[回车]"; break; 
case 32:keyName = "[空格]"; break; 
case 33:keyName = "[PageUp]"; break; 
case 34:keyName = "[PageDown]"; break; 
case 35:keyName = "[End]"; break; 
case 36:keyName = "[Home]"; break; 
case 37:keyName = "[方向键左]"; break; 
case 38:keyName = "[方向键上]"; break; 
case 39:keyName = "[方向键右]"; break; 
case 40:keyName = "[方向键下]"; break; 
case 46:keyName = "[删除]"; break; 
default:keyName = ""; break; 
} 
keystring += keyName; 
} 
$("content").innerHTML=keystring; 
} 
function keyup(e) 
{ 
$("content").innerHTML=keystring; 
} 
document.onkeypress=keypress; 
document.onkeydown =keydown; 
document.onkeyup =keyup; 
</script> 
<input type="text" /> 
<input type="button" value="清空记录" onclick="$(‘content').innerHTML = ";keystring = ";"/> 
<br/>请按下任意键查看键盘响应键值:<span id="content"></span> 
</BODY> 
</HTML> 

详细出处参考:http://www.jb51.net/article/25052.htm
原文地址:https://www.cnblogs.com/lhws/p/2801413.html