How can I capture keyboard events are from which keys?
Question
I googled and got the following codes on the Net.However, when I press a keyboard key,it is not displaying me an alert box. I want to get which character I have pressed in the alert box. How do I fix this?
<script type="text/javascript">
var charfield=document.getElementById("char")
charfield.onkeydown=function(e){
var e=window.event || e;
alert(e.keyCode);
}
</script>
</head>
<body id="char">
</body>
</html>
4 answers
solution1
9 ACCPTED 2011-06-28 10:31:40
If you want to get the character typed, you must use the keypress event rather than the keydown event. Something like the following:
var charfield = document.getElementById("char");
charfield.onkeypress = function(e) {
e = e || window.event;
var charCode = (typeof e.which == "number") ? e.which : e.keyCode;
if (charCode > 0) {
alert("Typed character: " + String.fromCharCode(charCode));
}
};
solution2
5 2011-06-28 10:23:04
try this jquery code
$("body").keypress(function(e){
alert(e.which);
});
solution3
1 2012-06-22 19:47:57
I can't off the top of my head think of a good situation in which to use the "on some event" method of a DOM element to deal with events on that element.
The best practice is to use addEventListener (or attachEvent in older versions of Internet Explorer) like so:
charfield.addEventListener('keydown', function (e) { alert(e.keyCode); }, false);
If you want to account for attachEvent as well:
(function (useListen) {
if (useListen) {
charfield.addEventListener('keydown', alertKeyCode, false);
} else {
charfield.attachEvent('onkeydown', alertKeyCode);
}
})(charfield.addEventListener);
function alertKeyCode(e) {
alert(e.keyCode);
}
solution4
1 2011-06-28 10:21:14
You'll get the appropriate key code:
charfield.onkeydown=function(evt){
var keyCode = (evt.which?evt.which:(evt.keyCode?evt.keyCode:0))
alert(keyCode);
}
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