I'd like to restrict keys that can be pressed.
$('.txtComments').keydown(function (event) {
var keys = new Array();
keys[0] = "8";
keys[1] = "46";
keys[2] = "37"
keys[3] = "39"
if(!(....)) //Check whether the keyCode is either of 8, 46, 37, or 39.
{
event.preventDefault();
}
});
Thanks for helping
The simplest (and fastest) here would be to use an object as map :
var keys = {};
keys[8] = true;
...
if (!keys[event.which]) {
...
Note that I suggest to use event.which instead of the keycode for better compatibility.
There are so many ways to implement this:
Just hard code it:
var keyCode = event.which;
if (keyCode != 8 && keyCode != 46 ...)
or check an array:
var keys = [8, 46, ...];
if (keys.indexOf(keyCode) < 0)
or the jQuery equivalent:
if ($.inArray(keyCode, keys) < 0)
or check an object:
var keys = { 8: 1, 46: 1, ... }
if (! (keyCode in keys) ) // or if (!keys[keyCode])
or a switch:
switch (keyCode) {
case 8: case 46: ...
// do nothing
break;
default:
event.preventDefault();
}
jQuery provides the utility method jQuery.inArray() to check if an array contains a value.
if(!keys.in_array(event.keyCode));
And change your keydown to keypress
<script type="text/javascript">
// Benoit Asselin - http://www.ab-d.fr
Array.prototype.in_array = function(p_val) {
for(var i = 0, l = this.length; i < l; i++) {
if(this[i] == p_val) {
return true;
}
}
return false;
}
</script>
You can use:-
var keys = [];
keys[8] = keys[4] = keys[37] = keys[39] = true;
if(keys[keyval]){
}
var keys = [8,46,37,39];, then you can use$.inArrayandevent.which$.inArraylet excludeCode = [20, 16, 17, 18, 32]if ( excludeCode.includes(event.which) ) {}