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:

 <input type="number" maxlength="2" min="0" max="99"/>

Instead of limiting the number of digits or the value of the number entered, the number is just left as it was typed in on iPhone 4. This markup works on most other phones we tested.

What gives?

Any workarounds?

If it is important to the solution, we use jQuery mobile.

Thanks!

Endicott

Answer 1

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">

Higbee

Hi! This method is working fine, if I restrict user up to 1/2/3 characters, but as soon as I go to the limit of 4 or above, the solution breaks. I guess the problem is because of addition of ',' in the number field, but not sure. Can you please check this solution for 4 or more characters. – Dinodinoflagellate

Sadly, I ended up relying on javascript/jQuery for this. I couldn't use type="range" because that has a different semantic. – Endicott

Not on keydown : else no copy/paste – Nibble

Use substring() instead of substr(), developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…. – Tarnish

Answer 2

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();
    }
}

Hadwin

Thanks, Buddy @Hadwin Btw Why we need maxlength="2" min="0" max="99" here ...?? With out them it Works Fine i guess :) – Creativity

maxlength attr do not work in input with type="number" – Hadwin

Answer 3

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));
    };
});

Burweed

This should be the accepted answer! – Link

Answer 4

According to MDN, maxlength is not used for numbers. Have you tried just:

<input type="number" min="0" max="99" />

OR

<input type="range" min="0" max="99" />

Fritzfritze

late to the game but how did this get 4 upvotes? deffo doesn't work – Rhumb

@TheWalrus but it does. – Link

Answer 5

Check this out, it works for me;

Is there a minlength validation attribute in HTML5?

Conjoint

pattern=".{4,4}" : Great – Nibble

Answer 6

as Andrew said you need to change the type to range, beside that you are going to have problems with IE and FF and probably old ipad browser because that's from HTML 5, and it's a "Kind New". Take a look to this person who tried the range with JS, Specify range of numbers to input in number field using javascript

Colman

Answer 7

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

Pinkham

Answer 8

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));
    };
});

Burgle

Answer 9

I use input event listener

var storeName = document.getElementById('storeName')
var storeNameCounter = document.getElementById('storeNameCounter')       
    storeName.addEventListener('input', (event) => {
        var max_chars = 50         
        if(event.target.value.length > max_chars) {
        event.target.value = event.target.value.substr(0, max_chars)
        }
        storeNameCounter.innerHTML = `${event.target.value.length}/50`       
    })

<input type="text" 
    id="storeName"
    name="store_name" 
    class="store_name"
    placeholder="store name" 
    x-moz-errormessage="This field should not be left blank." 
    maxlength="500" required>   
<span id="storeNameCounter" class="store_name_counter">0/50</span>  

Wyrick

By far the best answer – Hobo

Answer 10

I know this question is one year old, but I don't prefer the selected answer. Because the way it works is that it shows the character that is typed and then removes it.

In contrast I will propose another way which is similar to Will's, it is just better in the way that it prevents the character from being shown. Also I've added an else if block to check if the character is a number and then it is a good function to validate the number fields.

HTML

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

JS

function limit(element)
{
    var max_chars = 2;
    if (arguments[1].char !== "\b" && arguments[1].key !== "Left" && arguments[1].key !== "Right") {
        if (element.value.length >= max_chars) {
            return false;
        } else if (isNaN(arguments[1].char)) {
            return false;
        }
    }
}

Stelle

Answer 11

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));
    }
});

Debbydebee

Answer 12

My solution using jQuery:

JS

function maxlength(event)
{
    const ele = event.target;
    const maxlength = ele.maxLength;
    const value = ele.value;
    if (event.type == 'keypress')
    {
        if (value.length >= maxlength)
        {
            event.preventDefault();
        }
    }
    else if (event.type == 'keyup')
    {
        if (value.length > maxlength)
        {
            ele.value = value.substring(0, maxlength);
        }
    }
}

$('input[type=number][maxlength]').on('keypress keyup', maxlength);

HTML

<input type="number" maxlength="2">

Apostil