jQuery Validation Plugin

jQuery Validation Plugin library sources https://jqueryvalidation.org/

jQuery Validation Plugin - Form validation made easy.

The jQuery Validation Plugin provides drop-in validation for your existing forms, while making all kinds of customizations to fit your application really easy.

Getting Started

Downloading the prebuilt files

Prebuilt files can be downloaded from https://jqueryvalidation.org/

Downloading the latest changes

The unreleased development files can be obtained by:

1. Downloading or Forking this repository
2. Setup the build
3. Run grunt to create the built files in the "dist" directory

Including it on your page

Include jQuery and the plugin on a page. Then select a form to validate and call the validate method.

<form>
 <input required>
</form>
<script src="jquery.js"></script>
<script src="jquery.validate.js"></script>
<script>
    $("form").validate();
</script>

Alternatively include jQuery and the plugin via requirejs in your module.

define(["jquery", "jquery.validate"], function( $ ) {
 $("form").validate();
});

For more information on how to setup a rules and customizations, check the documentation.

Reporting issues and contributing code

See the Contributing Guidelines for details.
IMPORTANT NOTE ABOUT EMAIL VALIDATION. As of version 1.12.0 this plugin is using the same regular expression that the HTML5 specification suggests for browsers to use. We will follow their lead and use the same check. If you think the specification is wrong, please report the issue to them. If you have different requirements, consider using a custom method. In case you need to adjust the built-in validation regular expression patterns, please follow the documentation.
IMPORTANT NOTE ABOUT REQUIRED METHOD. As of version 1.14.0 this plugin stops trimming white spaces from the value of the attached element. If you want to achieve the same result, you can use the normalizer that can be used to transform the value of an element before validation. This feature was available since v1.15.0. In other words, you can do something like this:

$("#myForm").validate({
 rules: {
  username: {
   required: true,
   // Using the normalizer to trim the value of the element
   // before validating it.
   //
   // The value of `this` inside the `normalizer` is the corresponding
   // DOMElement. In this example, `this` references the `username` element.
   normalizer: function(value) {
    return $.trim(value);
   }
  }
 }
});

from  https://github.com/jquery-validation/jquery-validation