Form In Ruby on Rails: Understand How To Create It

Form In Ruby on Rails: Understand How To Create It

Form In Ruby on Rails is a crucial part of web development, allowing users to input and submit data to the server. 

In Ruby on Rails, creating forms is a fundamental skill for developers.

It is important to have knowledge of form creation and different features with Rails framework, almost all businesses prefer to add contact, registration, or any other form to collect visitors data.

In this article, we’ll dive into the process of creating forms in Ruby on Rails, from understanding the basics to implementing more advanced features. 

Whether you’re a seasoned developer or just starting, this guide will help you grasp the concept of forms in the Rails framework.

Form in Ruby on Rails: Overview

Forms are essential for interacting with users and gathering data. 

In Ruby on Rails, forms are built using HTML and form helpers provided by the framework. 

These form helpers simplify the process of generating form elements and handling user input.

What is a Form?

A web form is a method of sending data to a server; it is not a Rails concept. 

Although there are numerous different ways to accomplish this, utilizing the <form> tag entails sending data in a normal manner. It denotes high accessibility, device and browser support, and so on.

That works. Missing rails. void of JavaScript. Data can be submitted to another URL directly from the browser.

Page Title
Hire RoR Developers on Hourly or Monthly Basis

The hourly rates start at $20/hour

So Why Need Rails?

We don’t appear to require Rails in order to transmit any data to the server.

However, Rails includes a helper that will automatically build the aforementioned form in order to save repeated, error-prone copying and pasting, plus:

  • authenticity_token for security reasons
  • Consistent classes and ids
  • consistent “name” tags
  • to disable the submit button after it has been pushed (through JavaScript library named Rails-ujs)

To create forms, Rails has helpers:

  • form_for (softly deprecated)
  • form_tag (softly deprecated)
  • form_with (new standard)

In older gem or Rails projects, you may come across form_for and form_tag, but form_with is now the de facto norm. Therefore, form_with is the only aid that matters for any new project.

Let’s examine how Rails handles the straightforward form above now:

<# This is what you write in your Rails template file #>  

  <%= form_with scope: “book”, url: “/books” do |form| %>  

  <%= form.text_field :title %>  

  <%= form.submit “Create” %>  

<% end %>  

<# This is the generated HTML you can view in your browser #>  

<form class=”new_book” id=”new_book” action=”/books” method=”post”>  

  <input name=”utf8″ type=”hidden” value=”✓”>  

  <input type=”hidden” name=”authenticity_token” value=”…”>  

  <input type=”text” name=”book[title]” id=”book_title”>  

  <input type=”submit” name=”commit” value=”Create” data-disable-with=”Create”>  


What you can see from here is as follows:

  • In order for Rails to properly decode your form field on the server-side, it must “force” the encoding using a standard utf8.
  • POST is the default REST method (attribute method=”post” in the form tag).
  • For security purposes, the authentication_token has a hidden field.
  • The text field’s “name” and “id” are correctly written for you.
  • In order to manage the situation where there are several submit buttons, the submit field contains a name (“commit”).
  • Rails-ujs will leverage the “data-disable-with” property that already exists in the submit field to disable the submit button once it has been clicked.
  • Avoiding numerous submissions is essential. Consider the scenario in which your consumer clicks the “pay” button; this user surely doesn’t want to make multiple payments.

It is tiresome and highly risky to use form without Rails helper.

If you are thinking of initiating your project with Ruby on Rails, then you must hire the best ruby on rails backend developer to develop a user-friendly app.

Page Title
Hire RoR Developers on Hourly or Monthly Basis

The hourly rates start at $20/hour

Setting Up Your Rails Application

Before diving into creating forms, ensure you have a Ruby on Rails application set up. 

You can start a new project using the rails new command. 

Make sure you have the necessary dependencies installed.

We are happy to help you with setting up your Rails application! Here’s a step-by-step guide:

Step 1: Install Prerequisites

Before you start setting up your Rails application, make sure you have the following prerequisites installed:


Rails is a Ruby framework, so you’ll need Ruby installed on your system. You can download it from the official Ruby website or use a version manager like RVM or rbenv.


RubyGems is the package manager for Ruby. It usually comes with a Ruby installation, but make sure it’s up to date by running gem update –system.


Bundler is used to manage Ruby gem dependencies. Install it by running gem install bundler.


Rails relies on a JavaScript runtime for asset compilation. Node.js is a popular choice. From the official Node.js website, you can download it.


Yarn is a package manager for JavaScript. You’ll need it to manage JavaScript dependencies in your Rails application. Install it using npm: npm install -g yarn.

Step 2: Install Rails

Once you have the prerequisites in place, you can install Rails using the following command:

gem install rails

After the installation is complete, you can verify the installation by running:

rails –version

Step 3: Create a New Rails Application

Now that Rails is installed, you can create a new Rails application by navigating to your desired project directory and running:

rails new YourAppName

YourAppName should be changed to the name you like for your application.

Step 4: Configure the Database

By default, Rails uses SQLite as the database. You can configure the database settings in the config/database.yml file.

If you want to use a different database (e.g., MySQL or PostgreSQL), make sure to update the Gemfile with the appropriate database adapter and run bundle install.

Step 5: Set Up the Database

After configuring the database, run the following command to create the database tables:

rails db:create

Step 6: Start the Server

You’re almost there! Navigate to your application’s directory and start the Rails server:

cd YourAppName

rails server

Your Rails application will now be accessible at http://localhost:3000.

Congratulations! You’ve successfully set up a basic Rails application. 

From here, you can start building and customizing your application according to your requirements.

But, if you are not so familiar with coding and have more knowledge on business ideas, then you should contact ruby on rails development agency for better support and worthwhile development outcomes.

Generating a Basic Form 

To create a form, you’ll need to generate a view that contains the form elements. 

Rails provides several form helpers like form_for and form_tag to assist in this process. 

These helpers automatically generate the required HTML and handle form submission.

Providing Background Information

Let’s imagine you want to generate a new instance of your Post model. You may make a form for it in Rails 4 using the form_for view helper:

<%= form_for @post do |form| %>

 <%= form.text_field :author %>

 <%= form.submit “Create” %>

<% end %>

<form class=”new_post” id=”new_post” action=”/posts” accept-charset=”UTF-8″ method=”post”>

 <input name=”utf8″ type=”hidden” value=”✓”>

 <input type=”hidden” name=”authenticity_token” value=”…”>

 <input type=”text” name=”post[author]” id=”post_author”>

 <input type=”submit” name=”commit” value=”Create” data-disable-with=”Create”>


The block’s variable form is a FormBuilder object that contains details about the model object supplied to form_for and signified by :post.

What occurs if you need to create a form but don’t have a model instance to base it on? We have the form_tag helper in Rails:

<%= form_tag “/posts” do %>

 <%= text_field_tag “post[author]” %>

 <%= submit_tag “Create” %>

<% end %>

<form action=”/posts” accept-charset=”UTF-8″ method=”post”>

 <input name=”utf8″ type=”hidden” value=”✓”>

 <input type=”hidden” name=”authenticity_token” value=”…”>

 <input type=”text” name=“post[author]” id=“post_author”>

 <input type=”submit” name=”commit” value=“Create” data-disable-with=“Create”>


This second form doesn’t contain a FormBuilder object. You must use the appropriate input tag, such as text_field_tag, for each field you need to add to the form.


As demonstrated in the aforementioned example, both situations construct an HTML form for posting.

form_for and form_tag are distinct from one another since the former has an underlying model instance while the latter does not.

Let’s now see how form_with could help us achieve the same goal:

<%= form_with model: @post do |form| %>

 <%= form.text_field :author %>

 <%= form.submit “Create” %>

<% end %>

<form action=”/posts” accept-charset=”UTF-8″ method=”post” data-remote=”true”>

 <input name=”utf8″ type=”hidden” value=”✓”>

 <input type=”hidden” name=”authenticity_token” value=”…”>

 <input type=”text” name=”post[author]”>

 <input type=”submit” name=”commit” value=”Create” data-disable-with=”Create”>


<%= form_with url: “/posts” do |form| %>

 <%= form.text_field :author %>

 <%= form.submit “Create” %>

<% end %>

<form action=”posts” accept-charset=”UTF-8″ method=”post” data-remote=”true”>

 <input name=”utf8″ type=”hidden” value=”✓”>

 <input type=”hidden” name=”authenticity_token” value=”…”>

 <input type=”text” name=”author”>

 <input type=”submit” name=”commit” value=”Create” data-disable-with=”Create”>


Adding Form Elements

Within the form view, you can add various form elements such as text fields, radio buttons, checkboxes, and more. 

Form helpers like text_field, radio_button, and check_box make this task straightforward.

Form Helpers

Rails form helpers offer a convenient way to generate HTML for form elements. 

They also assist in binding form elements to models, which is crucial for data submission and retrieval.

Page Title
Hire RoR Developers on Hourly or Monthly Basis

The hourly rates start at $20/hour

Working with Form Models

Form models play a significant role in handling form data. 

They act as an intermediary between the controller and the database, validating and saving data.

Form Objects

Form objects provide an organized approach to handle complex forms. 

They encapsulate form-related logic, validations, and interactions, keeping controllers cleaner and more manageable.

Strong Parameters

Rails employs strong parameters to enhance security by whitelisting the allowed parameters before saving them to the database. This prevents malicious data from being injected.

Form Partial and Reusability

Using form partials enhances reusability and maintainability. 

Form partials are segments of forms that can be included in multiple views, reducing duplication of code.

Handling Form Submissions

Handling form submissions involves routing requests to the appropriate controller action and processing the data. 

Configure routes using the routes.rb file.

Creating Routes

Define Ruby on Rails routes for form submissions in the config/routes.rb file. 

Use the resources keyword or define custom routes based on your requirements.

Controller Actions

Controller actions process the form data, validate it, and interact with the model. 

Use actions like new, create, and update to manage form submissions.

Form Validation and Error Handling 

Validating form data ensures that only accurate and appropriate data is stored in the database. 

Rails provides built-in validation methods that you can apply to model attributes.

Model Validations

Model validations, such as presence, length, and format, ensure that data adheres to specific rules before being saved. 

These validations help maintain data integrity.

Displaying Errors

When form submissions fail validation, errors need to be displayed to users. 

Rails offers easy ways to present errors next to the respective form fields, guiding users on necessary corrections.

Customizing Form Appearance

Aesthetic appeal and user experience are essential for forms. 

You can customize form appearance using CSS to match your application’s design.

CSS Styling

Apply CSS styles to form elements to achieve the desired look and feel. 

This includes altering colors, fonts, spacing, and layout.

Bootstrap Integration

Integrating Bootstrap, a popular CSS framework, can simplify and enhance the visual aspect of your forms. 

Bootstrap provides pre-designed styles and components.

File Uploads with Forms 

Sometimes, forms require users to upload files. Rails facilitates this through libraries like CarrierWave, making file uploads seamless.

Configuring CarrierWave

Integrate CarrierWave into your Rails application by adding it to your Gemfile and running bundler. 

Configure the storage location for uploaded files.

Uploading Files

Create a file upload field in your form using the file_field helper. 

Configure the CarrierWave uploader to manage uploaded files.

AJAX and Remote Forms 

AJAX and remote forms allow form submission without reloading the entire page. This enhances user experience and makes applications feel more dynamic.

Unobtrusive JavaScript

Rails relies on unobtrusive JavaScript to handle AJAX requests. 

This approach keeps your HTML clean and separates JavaScript behaviour from the structure.

Updating Partials

AJAX-enabled forms can update specific parts of a page, known as partials, without refreshing the entire content. This creates a smoother, faster user experience.

Nested Forms

Nested forms enable users to submit data related to associated models. This is especially useful for scenarios where multiple sets of data are interconnected.

Creating Associations

Set up associations between models using relationships like has_many and belongs_to. This establishes the foundation for nested forms.

Building Nested Forms

Implement nested forms by using the fields_for helper. This helper creates form fields for associated models within the parent form.

Internationalization of Forms

For global applications, internationalization (i18n) is crucial. Translate form content and handle date and time formats to accommodate various regions.

Translating Form Content

Rails provides i18n features to translate form labels, placeholders, and error messages into different languages.

Date and Time Formats

Adapt date and time formats in forms according to different locales, ensuring consistency and proper understanding by users.

Form Security

Form security is paramount to prevent attacks and unauthorized access.

Rails offers protection against common vulnerabilities like Cross-Site Scripting (XSS) and Cross-Site Request Forgery (CSRF).

Cross-Site Scripting

Protect your forms from XSS attacks by escaping user-generated content and using Rails helpers that automatically sanitize data.

Cross-Site Request Forgery

Prevent CSRF attacks by using Rails’ built-in mechanisms like authenticity tokens, which verify the origin of form submissions.

Testing Forms

Thoroughly testing your forms is essential to ensure they function as intended and handle various scenarios appropriately.

Unit Testing

Write unit tests to evaluate individual form components, such as validations, form helpers, and controller actions.

Integration Testing

Perform integration tests to simulate real user interactions and ensure that form submissions are processed correctly.


Creating forms in Ruby on Rails is a critical skill for developers. 

From basic form generation to handling complex features like file uploads and nested forms, this guide has covered essential aspects of form development. 

With the knowledge gained from this article, you’re well-equipped to create interactive and user-friendly forms that enhance your Rails applications.

Contact the best ruby on rails consulting experts to get more information and knowledge about exciting features for your upcoming or existing project. This step will help a lot. 

Page Title
Hire RoR Developers on Hourly or Monthly Basis

The hourly rates start at $20/hour

Frequently Asked Questions (FAQs)

No, you can style forms using custom CSS. However, frameworks like Bootstrap offer pre-designed styles that can save time.

Nested forms are best suited for cases where there's a parent-child relationship between models.

Rails provides internationalization (i18n) features to translate form content, making it adaptable to different languages.

Certainly! Check out the Rails documentation and online tutorials for in-depth information on form development techniques.

Mitul Patel
Mitul Patel

Mitul Patel, Founded RORBits, one of the Top Software Development Company in 2011 offer mobile app development services across the globe. His visionary leadership and flamboyant management style have yield fruitful results for the company.

Leave a Reply

Your email address will not be published.Required fields are marked *