CODEWITHSUNDEEP
javascripthtmlinputnumbers
bool3max
bool3max

Reputation: 2865

How to restrict the amount of numbers allowed in the html number input (live)?

Basically, I have a number input field on my page, and I want users to only be able to insert 4 digits in the field. I know I can do something like this:

<input type="number" max="9999">

But the browser is going to check if the input is correct only when I press the "submit" button. What I want to do is : Let's say that the user types "1234" in the box, and after that he tries to type "1" or any other number. I want him to not be able to do that. Basically when he keeps pressing any of the buttons/letters, I want them to simply not appear in the box.

How can I achieve this?

Upvotes: 4

Views: 1003

Answers (5)

Sarath Chandra
Sarath Chandra

Reputation: 1888

Sweet and simple.

<input id="a" type="text" maxLength = "4" 
onkeypress='return event.charCode > 48 && event.charCode < 57'>

Note: Solution based on a community wiki : HTML Text Input allow only Numeric input

Upvotes: 1

Animesh Kumar
Animesh Kumar

Reputation: 69

var specialKeys = new Array();
        specialKeys.push(8); //Backspace
        $(function () {
            $("#a").bind("keypress", function (e) {
                if(this.value.length>3){ return false}
                var keyCode = e.which ? e.which : e.keyCode
                var ret = ((keyCode >= 48 && keyCode <= 57) || specialKeys.indexOf(keyCode) != -1);

                return ret;
            });
            $("#a").bind("paste", function (e) {
                return false;
            });
            $("#a").bind("drop", function (e) {
                return false;
            });
        });

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

Upvotes: 2

Yan
Yan

Reputation: 481

    <input type="number" id="userNumber">
        <input type="submit" id="numberSubmit" onclick="CheckValid()">
        <label id="warningMessage"></label>
        <script>
            function CheckValid(){
            var number = document.getElementById("userNumber").value;
            if(isNaN(number) || number.length != 4)
            {
                document.getElementById("warningMessage").innerHTML = "Invalid";
            }   
            else{
                document.getElementById("warningMessage").innerHTML = "Valid";
            }
            }
        </script>

Upvotes: 1

vinayakj
vinayakj

Reputation: 5681

var numberInput = document.getElementById('a');

numberInput.onkeypress = function(){
  console.log(this.value.length)
  if(this.value.length>3)
    return false
}
<input id="a" type="number">

For making it generalised, use below code

var inputs = document.querySelectorAll('.restrictLength');

for( i  in inputs){
   inputs[i].onkeypress = function(){
         console.log(this.id,this.value.length,this.getAttribute('data-restrict-to'));
         if(this.value.length>Number(this.getAttribute('data-restrict-to'))-1)
           return false
}

}
<input id="a" class="restrictLength" type="number" data-restrict-to="4"> restrict to 4
<br/>
<br/>
<input id="b" class="restrictLength" type="number" data-restrict-to="2"> restrict to 2

Upvotes: 5

Shrinivas Pai
Shrinivas Pai

Reputation: 7721

<input type="number" max="9999" maxlength="4">

Upvotes: -1

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