How do i allow special characters such as hyphen,ma,slash,space key,backspace key,delete key along with alphanumeric values and restrict the rest in jQuery?
As this criteria(allowed characters/input values) varies from field to field, i would like to make it as a utility method which accepts input field id and allowed characters as parameters. for example: limitCharacters(textid, pattern)
How do i allow special characters such as hyphen,ma,slash,space key,backspace key,delete key along with alphanumeric values and restrict the rest in jQuery?
As this criteria(allowed characters/input values) varies from field to field, i would like to make it as a utility method which accepts input field id and allowed characters as parameters. for example: limitCharacters(textid, pattern)
Share Improve this question edited Aug 16, 2012 at 11:30 Adi 5,1796 gold badges35 silver badges48 bronze badges asked Aug 16, 2012 at 11:23 net usernet user 5932 gold badges8 silver badges21 bronze badges 2- 1 Do you have any code samples of your attempts? – o01 Commented Aug 16, 2012 at 11:27
- Thanks you all for ur help... Now i need to pare non-english characters.. such as Azhari.. How do i do it with pattern match? Basically my application should support for both English and Azhari characters.. Here i am struck. Please Help me out... – net user Commented Aug 16, 2012 at 17:32
3 Answers
Reset to default 6You can just check the keyCode on keydown
and run preventDefault()
if match:
$('input').keydown(function(e) {
if (e.which == 8) { // 8 is backspace
e.preventDefault();
}
});
http://jsfiddle/GVb6L/
If you need to restrict to certain chars AND keyCodes + make it into a jQuery plugin, try something like:
$.fn.restrict = function( chars ) {
return this.keydown(function(e) {
var found = false, i = -1;
while(chars[++i] && !found) {
found = chars[i] == String.fromCharCode(e.which).toLowerCase() ||
chars[i] == e.which;
}
found || e.preventDefault();
});
};
$('input').restrict(['a',8,'b']);
http://jsfiddle/DHCUg/
I did something like this but in jQuery plugin format. This example will only allow numbers and full stops.
You can call this by writing:
$("input").forceNumeric();
And the plugin:
jQuery.fn.forceNumeric = function () {
return this.each(function () {
$(this).keydown(function (e) {
var key = e.which || e.keyCode;
if (!e.shiftKey && !e.altKey && !e.ctrlKey &&
// numbers
key >= 48 && key <= 57 ||
// Numeric keypad
key >= 96 && key <= 105 ||
// ma, period and minus, . on keypad
key == 190 || key == 188 || key == 109 || key == 110 ||
// Backspace and Tab and Enter
key == 8 || key == 9 || key == 13 ||
// Home and End
key == 35 || key == 36 ||
// left and right arrows
key == 37 || key == 39 ||
// Del and Ins
key == 46 || key == 45)
return true;
return false;
});
});
}
I would suggest using David solution for modifier keys like backspace and delete and this code below for characters:
var chars = /[,\/\w]/i; // all valid characters
$('input').keyup(function(e) {
var value = this.value;
var char = value[value.length-1];
if (!chars.test(char)) {
$(this).val(value.substring(0, value.length-1));
}
});
Also, I've experienced some problems with keydown
so I'd do it on keyup
.
Demo: http://jsfiddle/elclanrs/QjVGV/ (try typing a dot .
or semicolon ;
)