Java script validations

Rails
1

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

2

Does this degrade gracefully when users are not able to use Javascript?

3

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

required:
http://www.agilewebdevelopment.com/plugins/validation_reflection

Michael

–
Michael S.
mailto:[email protected]
http://www.schuerig.de/michael/

4

That was probably a dumb question… looks like it doesn’t affect
normal
flow.

5

On 12/5/06, Michael S. [email protected] wrote:

Have a look at my client-side validation plugin

http://www.agilewebdevelopment.com/plugins/client_side_validation

required:
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.

6

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:[email protected]
http://www.schuerig.de/michael/

7

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| %>
8

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.

9

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:[email protected]
http://www.schuerig.de/michael/