# Java script validations **URL:** \ **Category:** Rails\ **Created:** [December 5, 2006, 2:41pm UTC](https://www.ruby-forum.com/t/java-script-validations/78391 "2006-12-05T14:41:41Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 5, 2006, 2:41pm UTC](https://www.ruby-forum.com/t/java-script-validations/78391/1 "2006-12-05T14:41:41Z")
Hi Everyone, Can anyone tell, how to validate for empty fields (or) certain patterns using java script (client side validations) in Ruby on Rails?? I need to check whether the user has entered a “login id” and “password” before hitting the submit button. Thanks in advance… With Regards, Vasanth ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 5, 2006, 7:46pm UTC](https://www.ruby-forum.com/t/java-script-validations/78391/2 "2006-12-05T19:46:21Z")
Does this degrade gracefully when users are not able to use Javascript? ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 5, 2006, 6:46pm UTC](https://www.ruby-forum.com/t/java-script-validations/78391/3 "2006-12-05T18:46:14Z")
On Tuesday 05 December 2006 14:41, Vasanthakumar C. wrote: > Hi Everyone, > Can anyone tell, how to validate for empty fields (or) > certain patterns using java script (client side validations) in Ruby > on Rails?? I need to check whether the user has entered a “login id” > and “password” before hitting the submit button. Have a look at my client-side validation plugin [http://www.agilewebdevelopment.com/plugins/client\_side\_validation](http://www.agilewebdevelopment.com/plugins/client_side_validation) required: [http://www.agilewebdevelopment.com/plugins/validation\_reflection](http://www.agilewebdevelopment.com/plugins/validation_reflection) Michael – Michael S. [mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [http://www.schuerig.de/michael/](http://www.schuerig.de/michael/) ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 5, 2006, 7:48pm UTC](https://www.ruby-forum.com/t/java-script-validations/78391/4 "2006-12-05T19:48:21Z")
That was probably a dumb question… looks like it doesn’t affect normal flow. ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 5, 2006, 8:48pm UTC](https://www.ruby-forum.com/t/java-script-validations/78391/5 "2006-12-05T20:48:29Z")
On 12/5/06, Michael S. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Have a look at my client-side validation plugin > > [http://www.agilewebdevelopment.com/plugins/client\_side\_validation](http://www.agilewebdevelopment.com/plugins/client_side_validation) > > required: > [http://www.agilewebdevelopment.com/plugins/validation\_reflection](http://www.agilewebdevelopment.com/plugins/validation_reflection) Cool michael, but where I put the code to validate? I used to write my own javascript validators and put them inside a in my layouts. – Fernando L. ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 6, 2006, 12:11am UTC](https://www.ruby-forum.com/t/java-script-validations/78391/6 "2006-12-06T00:11:07Z")
On Tuesday 05 December 2006 20:39, Fernando L. wrote: > in my layouts. > As long as you don’t need rather special validations there is no need to > write _any_ JavaScript code of your own. You automatically get > validations corresponding to - validates\_presence\_of - validates\_length\_of - validates\_numericality\_of - validates\_inclusion\_of - validates\_format\_of - as far as regular expressions are matched the same in Ruby and JavaScript If you do need more special validations, see “Custom Checking” in the README. Judging from the questions I’ve got since I published the plugin, the trickier part is to tell the user there’s something wrong with their entered data. The validator runs all the time, not just when the user tries to submit a form. What it normally does is to add/remove “invalid” to/from the class attribute of input elements (text fields, selects, radio buttons). This change, of course is not visible to the user. You can make it visible with a short bit of CSS .invalid { border: 1px solid #f00; } Actually, I don’t recommend doing it exactly like this. But the specifics of error notification depend on the needs of your application. There’s also a way to supply a callback function to the validator that is called whenever the validation status of the form changes. For the details see the README and follow up with more specific questions. Michael – Michael S. [mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [http://www.schuerig.de/michael/](http://www.schuerig.de/michael/) ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 6, 2006, 6:56am UTC](https://www.ruby-forum.com/t/java-script-validations/78391/7 "2006-12-06T06:56:38Z")
Chris. Here’s what I did to get it working 1. In the plugin/client\_side\_validation/install.rb only include the two js files ActionView::Helpers::AssetTagHelper::register\_javascript\_include\_default(‘validator’) ActionView::Helpers::AssetTagHelper::register\_javascript\_include\_default(‘validators-en’) (This is included when defining \<%= javascript\_include\_tag :defaults %\> in the layout) 2. Add installForAllValidatedForms to the view 1. set the form class as ‘validated’ (I’m using edge rails) \<% form\_for(:article, :url =\> articles\_path, :html =\> {:class =\> “validated”}) do |f| %\> ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 6, 2006, 2:25am UTC](https://www.ruby-forum.com/t/java-script-validations/78391/8 "2006-12-06T02:25:25Z")
Ok…I’m trying to get this thing working, and I think I’m missing something fundamental. Do you have a simple example available to look at? Here’s what I’ve done: 1. Install Plugins script/plugin install svn://rubyforge.org//var/svn/clientsidevali/client\_side\_validation/trunk script/plugin install svn://rubyforge.org//var/svn/valirefl/validation\_reflection/trunk 2. Create a model class Post \< ActiveRecord::Base validates\_length\_of :title, :within =\> 3…20 end 3. Create a controller class PostsController \< ApplicationController def create Post.create(params[:post]) end end 4. Create a view \<%= stylesheet\_link\_tag 'posts' %\> \<%= javascript\_include\_tag :defaults %\> \<%= form\_tag url = {:action =\> "create"}, options = {:class =\> 'validated'}%\> Title \<%= text\_field 'post', 'title' %\> \<%= submit\_tag %\> \<%= end\_form\_tag %\> 1. Create /public/javascripts/application.js Form.Validator.installForAllValidatedForms(); 2. Create a stylesheet .invalid { border: 1px solid #f00; } 3. Go to the browser, enter invalid input and expect something to happen. ---
**Author:** ![vasan\_cec](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/258eb7/32.png) [@vasan\_cec](https://www.ruby-forum.com/u/vasan_cec)\ **Post date:** [December 6, 2006, 10:56am UTC](https://www.ruby-forum.com/t/java-script-validations/78391/9 "2006-12-06T10:56:55Z")
On Wednesday 06 December 2006 06:56, Chris Douglas wrote: > Chris. Here’s what I did to get it working > > 1. In the plugin/client\_side\_validation/install.rb only include the > two js files > ActionView::Helpers::AssetTagHelper::register\_javascript\_include\_defa > ult(‘validator’) > ActionView::Helpers::AssetTagHelper::register\_javascript\_include\_defa > ult(‘validators-en’) > (This is included when defining \<%= > javascript\_include\_tag :defaults %\> in the layout) Thanks for pointing this out. I have changed the code (and README) so that none of the locale-specific validations are included by default. Therefore, after updating the plugin, you have to include the necessary file explicitly in your layout. So \<%= javascript\_include\_tag :defaults %\> has to become \<%= javascript\_include\_tag :defaults %\> \<%= javascript\_include\_tag ‘validators-en’ %\> > 1. Add installForAllValidatedForms to the view I recommend adding that line of JavaScript to public/javascripts/application.js as that file is included by default > 1. set the form class as ‘validated’ (I’m using edge rails) > \<% form\_for(:article, :url =\> articles\_path, :html =\> {:class =\> > “validated”}) do |f| %\> Yes. Michael – Michael S. [mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [http://www.schuerig.de/michael/](http://www.schuerig.de/michael/)