CODEWITHSUNDEEP
javascriptjqueryhtmlinput
Ris
Ris

Reputation: 1912

Prevent users from submiting a form when they enter same numbers in a row

I have a form here

<form action="/customer" method="post" id="customer-summary">
    <input type="text" size="9" maxlength="9" id="my_account" name="my_account" value="" >
    <input type="submit" value="submit">
</form>

and here what I want is to prevent the form submit when users enter the same 4 numbers in row. Right now its preventing users to submit when they enter same 2 numbers but not in the row.

jsFiddle: https://jsfiddle.net/m31h1zhg/

var inputNode = document.getElementById('my_account');
var customer_summary = document.getElementById('customer-summary');
customer_summary.addEventListener('submit', function(e) {
    console.log(is_unique(inputNode.value));
    if (!is_unique(inputNode.value)) {
        e.preventDefault();
        alert("prevent submit");
    }             
});

function is_unique(val) {
    for(var i = 0; i < val.length; i++) {
        if (val.indexOf(val.charAt(i)) != val.lastIndexOf(val.charAt(i))) {
            return false;
        }       
    }
    return true;
}

Right now I have 123145678 (same 2 numbers not in a row) which is what I don't want. I want the same 4 numbers in row be prevented, for example 111123412

How could I do this?

Upvotes: 0

Views: 45

Answers (1)

charsi
charsi

Reputation: 3817

You can validate the input with some regex like so

if(/\d*(\d)\1{3,}\d*/.test(value)){
    ....
}

https://jsfiddle.net/am1wabgf/

The regex looks for a digit thats being repeated 4 or more times and if so the test returns true in Javascript.

Also I changed the input type to 'number' instead of text so it automatically throws an error if the user enters any letters.

Upvotes: 1

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