JQuery Validation for Array of Input Elements

Sometimes we need to validate an array of input elements: For example –

[code language=”html”]
<form name="signupForm" class="cmxform" id="signupForm" method="get" action="">
<select name="category[]" id="cat_1">
<option value="">Select One</option>
<option value="1">aa</option>
<option value="2">bb</option>
<option value="3">cc</option>
<option value="4">dd</option>

<select name="category[]" id="cat_2">
<option value="">Select One</option>
<option value="5">ee</option>
<option value="6">ff</option>
<option value="7">gg</option>
<option value="8">hh</option>

<select name="category[]" id="cat_3">
<option value="">Select One</option>
<option value="9">ii</option>
<option value="10">jj</option>
<option value="11">kk</option>
<option value="12">ll</option>

<input class="submit" value="Submit" type="submit">
Now we will use jquery validation plugin jquery.validate.js for validating the form. The condition will be that user will have to choose category from each dropdown. The script for validation will be as below –
[code language=”js”]
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="jquery.validate.js"></script>
<script type="text/javascript">
$().ready(function() {
// validate the comment form when it is submitted
rules: {
"category[]": "required"
messages: {
"category[]": "Please select category",

Now the problem is that the readymade jquery.validate.js only validates the first element of category[]. So, we need to modify it a little bit.

In jquery.validate.js, we can find a function named checkForm, we have to modify it as below:
[code language=”js”]
checkForm: function() {
for ( var i = 0, elements = (this.currentElements = this.elements()); elements[i]; i++ ) {
if (this.findByName( elements[i].name ).length != undefined && this.findByName( elements[i].name ).length > 1) {
for (var cnt = 0; cnt < this.findByName( elements[i].name ).length; cnt++) {
this.check( this.findByName( elements[i].name )[cnt] );
} else {
this.check( elements[i] );
return this.valid();

Sandeep Kumar

Sandeep kumar is a web developer and a professinal blogger. He works for latest technologies and write articles what he learn. In ICodeHub he share web languages tutorials and other programming tips and tricks. if you need some help or have some suggestion then mail him at sandeep92pal@gmail.com without any hesitation. He believes in learning and sharing.