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<!-- ***********************************************************
Example 6-1
"Dynamic HTML:The Definitive Reference"
2nd Edition
by Danny Goodman
Published by O'Reilly & Associates ISBN 0-596-00316-1
http://www.oreilly.com
Copyright 2002 Danny Goodman. All Rights Reserved.
************************************************************ -->
<html>
<head>
<title>Keyboard Events and Codes</title>
<style type="text/css">
body {font-family:Arial, sans-serif}
h1 {text-align:right}
td {text-align:center}
</style>
<script language="JavaScript" type="text/javascript">
// array of table cell ids
var tCells = ["downKey", "pressKey", "upKey", "downChar", "pressChar", "upChar", "keyTarget", "character"];
// clear table cells for each key down event
function clearCells() {
for (var i = 0; i < tCells.length; i++) {
document.getElementById(tCells[i]).innerHTML = "—";
}
}
// display target node's node name
function showTarget(evt) {
var node = (evt.target) ? evt.target : ((evt.srcElement) ? evt.srcElement : null);
if (node) {
document.getElementById("keyTarget").innerHTML = node.nodeName;
}
}
// decipher key down codes
function showDown(evt) {
clearCells();
evt = (evt) ? evt : ((event) ? event : null);
if (evt) {
document.getElementById("downKey").innerHTML = evt.keyCode;
if (evt.charCode) {
document.getElementById("downChar").innerHTML = evt.charCode;
}
showTarget(evt);
}
}
// decipher key press codes
function showPress(evt) {
evt = (evt) ? evt : ((event) ? event : null);
if (evt) {
document.getElementById("pressKey").innerHTML = evt.keyCode;
if (evt.charCode) {
document.getElementById("pressChar").innerHTML = evt.charCode;
}
showTarget(evt);
var charCode = (evt.charCode) ? evt.charCode : evt.keyCode;
// use String method to convert back to character
document.getElementById("character").innerHTML = String.fromCharCode(charCode);
}
}
// decipher key up codes
function showUp(evt) {
evt = (evt) ? evt : ((event) ? event : null);
if (evt) {
document.getElementById("upKey").innerHTML = evt.keyCode;
if (evt.charCode) {
document.getElementById("upChar").innerHTML = evt.charCode;
}
showTarget(evt);
}
}
// set page-wide event listeners
document.onkeydown = showDown;
document.onkeypress = showPress;
document.onkeyup = showUp;
</script>
</head>
<body>
<h1>Key and Character Codes vs. Event Types</h1>
<hr>
<p>Enter some text with uppercase and lowercase letters:<br>
<form>
<input type="text" id="entry" size="60"
onkeydown="showDown(event)"
onkeypress="showPress(event)"
onkeyup="showUp(event)">
</textarea></p>
</form>
<table border="2" cellpadding="5" cellspacing="5">
<caption>Keyboard Event Properties</caption>
<tr><th>Data</th><th>keydown</th><th>keypress</th><th>keyup</th></tr>
<tr><td>keyCode</td>
<td id="downKey">—</td>
<td id="pressKey">—</td>
<td id="upKey">—</td>
</tr>
<tr><td>charCode</td>
<td id="downChar">—</td>
<td id="pressChar">—</td>
<td id="upChar">—</td>
</tr>
<tr><td>Target</td>
<td id="keyTarget" colspan="3">—</td>
</tr>
<tr><td>Character</td>
<td id="character" colspan="3">—</td>
</tr>
</table>
</body>
</html>
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