Validate Dynamically Added Input fields

Question

I have used this jquery validation plugin for the following form.

<script src="http://code.jquery.com/jquery-latest.js"></script>
<script type="text/javascript" src="http://jzaefferer.github.com/jquery-validation/jquery.validate.js"></script>

<script>
    $(document).ready(function(){
        $("#commentForm").validate();
    });

    function addInput() {
        var obj = document.getElementById("list").cloneNode(true);
        document.getElementById('parent').appendChild(obj);
    }
</script>

<form id="commentForm" method="get" action="">
    <p id="parent">
        <input id="list"  class="required" />
    </p>

    <input class="submit" type="submit" value="Submit"/>
    <input type="button" value="add" onClick="addInput()" />
</form>

When the add button is clicked a new input is dynamically added. However when the form is submitted only the first input field is validated. How can i validate dynamically added inputs? Thank you...

Answer 1

You should have 'name' attribute for your inputs. You need to add the rules dynamically, one option is to add them when the form submits.

And here is my solution that I've tested and it works:

<script type="text/javascript">
   $(document).ready(function() {
        var numberIncr = 1; // used to increment the name for the inputs

        function addInput() {
            $('#inputs').append($('<input class="comment" name="name'+numberIncr+'" />'));
            numberIncr++;
        }

        $('form.commentForm').on('submit', function(event) {

            // adding rules for inputs with class 'comment'
            $('input.comment').each(function() {
                $(this).rules("add", 
                    {
                        required: true
                    })
            });            

            // prevent default submit action         
            event.preventDefault();

            // test if form is valid 
            if($('form.commentForm').validate().form()) {
                console.log("validates");
            } else {
                console.log("does not validate");
            }
        })

        // set handler for addInput button click
        $("#addInput").on('click', addInput);

        // initialize the validator
        $('form.commentForm').validate();

   });


</script>

And the html form part:

<form class="commentForm" method="get" action="">
    <div>

        <p id="inputs">    
            <input class="comment" name="name0" />
        </p>

    <input class="submit" type="submit" value="Submit" />
    <input type="button" value="add" id="addInput" />

    </div>
</form>

Good luck! Please approve answer if it suits you!

Answer 2

Reset form validation after adding new fields.

function resetFormValidator(formId) {
    $(formId).removeData('validator');
    $(formId).removeData('unobtrusiveValidation');
    $.validator.unobtrusive.parse(formId);
}

Answer 3

You need to re-parse the form after adding dynamic content in order to validate the content

$('form').data('validator', null);
$.validator.unobtrusive.parse($('form'));

Answer 4

The one mahesh posted is not working because the attribute name is missing:

So instead of

<input id="list" class="required"  />

You can use:

<input id="list" name="list" class="required"  />

Modified version

Answer 5

jquery validation plugin version work fine v1.15.0 but v1.17.0 not work for me.

$(document).find('#add_patient_form').validate({
          ignore: [],
          rules:{
            'email[]':
            {
              required:true,
            },               
          },
          messages:{
            'email[]':
            {
              'required':'Required'
            },            
          },    
        });

Answer 6

In regards to @RitchieD response, here is a jQuery plugin version to make things easier if you are using jQuery.

(function ($) {

    $.fn.initValidation = function () {

        $(this).removeData("validator");
        $(this).removeData("unobtrusiveValidation");
        $.validator.unobtrusive.parse(this);

        return this;
    };

}(jQuery));

This can be used like this:

$("#SomeForm").initValidation();

Answer 7

$('#form-btn').click(function () {
//set global rules & messages array to use in validator
   var rules = {};
   var messages = {};
//get input, select, textarea of form
   $('#formId').find('input, select, textarea').each(function () {
      var name = $(this).attr('name');
      rules[name] = {};
      messages[name] = {};

      rules[name] = {required: true}; // set required true against every name
//apply more rules, you can also apply custom rules & messages
      if (name === "email") {
         rules[name].email = true;
         //messages[name].email = "Please provide valid email";
      }
      else if(name==='url'){
        rules[name].required = false; // url filed is not required
//add other rules & messages
      }
   });
//submit form and use above created global rules & messages array
   $('#formId').submit(function (e) {
            e.preventDefault();
        }).validate({
            rules: rules,
            messages: messages,
            submitHandler: function (form) {
            console.log("validation success");
            }
        });
});

Answer 8

Try using input arrays:

<form action="try.php" method="post">
    <div id="events_wrapper">
        <div id="sub_events">
            <input type="text" name="firstname[]" />                                       
        </div>
    </div>
    <input type="button" id="add_another_event" name="add_another_event" value="Add Another" />
    <input type="submit" name="submit" value="submit" />
</form>

and add this script and jQuery, using foreach() to retrieve the data being $_POST'ed:

<script>                                                                                    
    $(document).ready(function(){
        $("#add_another_event").click(function(){
        var $address = $('#sub_events');
        var num = $('.clonedAddress').length; // there are 5 children inside each address so the prevCloned address * 5 + original
        var newNum = num + 1;
        var newElem = $address.clone().attr('id', 'address' + newNum).addClass('clonedAddress');

        //set all div id's and the input id's
        newElem.children('div').each (function (i) {
            this.id = 'input' + (newNum*5 + i);
        });

        newElem.find('input').each (function () {
            this.id = this.id + newNum;
            this.name = this.name + newNum;
        });

        if (num > 0) {
            $('.clonedAddress:last').after(newElem);
        } else {
            $address.after(newElem);
        }

        $('#btnDel').removeAttr('disabled');
        });

        $("#remove").click(function(){

        });

    });
</script>

Answer 9

In case you have a form you can add a class name as such:

<form id="my-form">
  <input class="js-input" type="text" name="samplename" />
  <input class="js-input" type="text" name="samplename" />
  <input class="submit" type="submit" value="Submit" />
</form>

you can then use the addClassRules method of validator to add your rules like this and this will apply to all the dynamically added inputs:

$(document).ready(function() {
  $.validator.addClassRules('js-input', {
    required: true,
  });
  //validate the form
  $('#my-form').validate();
});

Answer 10

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/[email protected]/dist/jquery.validate.js"></script>

<script>
    $(document).ready(function(){
        $("#commentForm").validate();
    });

    function addInput() {

        var indexVal = $("#index").val();
        var index = parseInt(indexVal) + 1
        var obj = '<input id="list'+index+'" name=list['+index+']  class="required" />'
        $("#parent").append(obj);

        $("#list"+index).rules("add", "required");
        $("#index").val(index)
    }
</script>

<form id="commentForm" method="get" action="">
    <input type="hidden" name="index" name="list[1]" id="index" value="1">
    <p id="parent">
        <input id="list1"  class="required" />
    </p>
    <input class="submit" type="submit" value="Submit"/>
    <input type="button" value="add" onClick="addInput()" />
</form>