How to restrict number of characters that can be entered in HTML5 number input field on iPhone

Question

It seems that neither of the \"maxlength\", \"min\" or \"max\" HTML attributes have the desired effect on iPhone for the following markup:

Answer 1

you can use this code:

<input type="number" onkeypress="limitKeypress(event,this.value,2)"/>

and js code:

function limitKeypress(event, value, maxLength) {
    if (value != undefined && value.toString().length >= maxLength) {
        event.preventDefault();
    }
}

Answer 2

Example

JS

function limit(element)
{
    var max_chars = 2;

    if(element.value.length > max_chars) {
        element.value = element.value.substr(0, max_chars);
    }
}

HTML

<input type="number" onkeydown="limit(this);" onkeyup="limit(this);">

If you are using jQuery you can tidy up the JavaScript a little:

JS

var max_chars = 2;

$('#input').keydown( function(e){
    if ($(this).val().length >= max_chars) { 
        $(this).val($(this).val().substr(0, max_chars));
    }
});

$('#input').keyup( function(e){
    if ($(this).val().length >= max_chars) { 
        $(this).val($(this).val().substr(0, max_chars));
    }
});

HTML

<input type="number" id="input">

Answer 3

You can use JavaScript to check how many characters are in the box and if there are too many, remove one: http://www.webcodingtech.com/javascript/limit-input-text.php

Answer 4

This is Tripex answer optimized for allowing delete key, works when typing and on paste.

$(document).on("keyup", "#your_element", function(e) {
    var $that = $(this),
    maxlength = $that.attr('maxlength');
    if ($.isNumeric(maxlength)){
        if($that.val().length === maxlength) {
            e.preventDefault();
            // If keyCode is not delete key 
            if (e.keyCode !== 64) {
                return;
            }
        }
        $that.val($that.val().substr(0, maxlength));
    }
});

Answer 5

Here a more optimized jQuery version that caches the selectors. It also uses the maxlength attribute that is not supported by input type number.

// limits the input based on the maxlength attribute, this is by default no supported by input type number
$("input[type=number]").on('keydown keyup',function(){ 
    var $that = $(this),
    maxlength = $that.attr('maxlength')
    if($.isNumeric(maxlength)){
        $that.val($that.val().substr(0, maxlength));
    };
});

Answer 6

Another option with jQuery, but onkeypress event... ;)

$("input[type=number]").on('keypress',function(e) { 
    var $that = $(this),
    maxlength = $that.attr('maxlength')
    if($.isNumeric(maxlength)){
        if($that.val().length == maxlength) { e.preventDefault(); return; }

        $that.val($that.val().substr(0, maxlength));
    };
});