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JavaScript

Posted by Anna Litynska
Anna Litynska
2,346 Points

Form validation with Javascript

Hi all, I have a checkbox html form and I need a message to appear if I checked more than 2 options. How can I do it? Need help :) Thanks

<form>
    <p>
    Choose:
    <input type="checkbox" name="class" value="lux" checked="checked"> 1
    <input type="checkbox" name="class" value="sleep" > 2
    <input type="checkbox" name="class" value="coupe" > 3
    <input type="checkbox" name="class" value="platz" > 4
    <input type="checkbox" name="class" value="general"> 5
    </p>


</form>

1 Answer

Christopher Denny
Christopher Denny
10,460 Points
Christopher Denny
Christopher Denny
10,460 Points

I would suggest making it so that when a checkbox is click, it adds a class "active" or "checked" then write some Javascript so that if there are more than one items with the "active" class, it does what you're wanting. Heres an article for adding and removing classes http://jaketrent.com/post/addremove-classes-raw-javascript/

You can set the "onclick" event with HTML or Javascript http://www.w3schools.com/jsref/event_onclick.asp

To see if there are multiple of a class, you can check if a get Class

var checked = $('checked')

var checked = document.getElementsByClassName('checked')

has more than one item by testing if the get has more than one item in the array.

if(checked[1]){}

This will return true or false if there is a second item.

I hope this helps!

Anna Litynska
Anna Litynska
2,346 Points

Thanks a lot, I will try that