I need to detect whether the user has pressed the dot key in the numeric keypad. I’ve written this first draft that works for me:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head><title></title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript"><!--
(function($){
var knownCodes = [
[110, 46], // Firefox, IE, Chrome
[78, 46] // Opera
];
var pressedCodes = [null, null];
$.fn.comma = function(){
this.live("keydown", function(e){
pressedCodes = [e.which, null];
}).live("keypress", function(e){
pressedCodes[1] = e.which;
for(var i=0, len=knownCodes.length; i<len; i++){
if(pressedCodes[0]==knownCodes[i][0] && pressedCodes[1]==knownCodes[i][1]){
$("#log").append("<li>Decimal key detected</li>");
break;
}
}
});
return this;
};
$(function(){
$('<ol id="log"></ol>').appendTo("body");
});
})(jQuery);
jQuery(function($){
$(".comma input:text, .comma textarea").css("border", "1px solid black").comma();
});
//--></script>
</head>
<body>
<form action="" method="get" class="comma" size="20">
<p><input type="text"></p>
<p><textarea rows="3" cols="30"></textarea></p>
</form>
</body>
</html>
However, I can only test it in a Windows XP box with a Spanish keyboard. My questions are:
-
Is it safe to read from
e.which? I’m using it because bothe.keyCodeande.charCodereturnundefinedin at least one browser. -
Does the operating system affect these numeric codes in some manner or it’s only a browser stuff?
-
Do these codes depend on the keyboard layout?
Background info: I couldn’t find a jQuery plugin to remap numeric keypad so I’m writing my own.
Update
I’ll explain my exact need. Spanish keyboards that have a numeric keypad feature a . key. However, the decimal separator in Spanish is ,. That makes it annoying to type numbers in web applications. Some desktop apps like MS Excel remap this key so it inserts a comma. I’m trying to mimic that.
I’ve adapted a little script I’ve been using to post it here. That’s how I got the values for the knownCodes arrays:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head><title></title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript"><!--
(function($){
$.fn.showKeyCodes = function(){
var log = function(e){
$("<li></li>").text(e.type + "(): [keyCode, charCode, which]=[" + e.keyCode + ", " + e.charCode + ", " + e.which + "]").appendTo("#log");
}
this.live("keydown", function(e){
log(e);
}).live("keypress", function(e){
log(e);
}).live("keyup", function(e){
log(e);
});
return this;
};
$(function(){
$('<ol id="log"></ol>').appendTo("body");
});
})(jQuery);
jQuery(function($){
$(".showKeyCodes input:text, .showKeyCodes textarea").css("border", "1px solid black").showKeyCodes();
});
//--></script>
</head>
<body>
<form action="" method="get" class="showKeyCodes" size="20">
<p><input type="text"></p>
<p><textarea rows="3" cols="30"></textarea></p>
</form>
</body>
</html>
Type the . key in your numeric keypad (or whatever key replaces it in your keyboard layout) and the key that corresponds to the same character in the alphabetical keypad. The goal is to detect you clicked the first one and not the second one.
Your code doesn’t do anything on my end, so I’d say it probably does depend on keyboard layout. A quick check confirms that the output on my finnish qwerty keyboard is keycode 44, instead of the expected 46.