Rails form helpers cheatsheet

Form builder

Form builder

- form_for @post do |f|

Field names will be prefixed with post (the class name), and values will be derived from this object (eg, f.text_field :name from @post.name).

Options

- form_for @post, |
  url: { method: 'put', action: 'create' }, |
  html: { class: 'nifty_form' } |
  do |f|

Fields

Text

f.text_field :title
f.text_area :body, size: '60x12'

Checkbox

f.check_box :remember_me
f.label :remember_me, "Remember me"

Radio

f.radio_button :gender, 'male'
f.label :gender_male, "Male"

f.radio_button :gender, 'female'
f.label :gender_female, "Female"

Label

f.label :title
f.label :title, "Title"
f.label :title, "Title", class: "title"
f.label(:post, :terms) { "Accept terms" }

Submit button

f.submit "Create"

Hidden fields

f.hidden_field :id

Misc

The model

f.object

Fields for

= form_for @post do |f|
  = fields_for :author, @post.author do |ff|
    = ff.text_field :name

Select dropdowns

f.select :city_id, [['Lisbon',1], ['Madrid',2], ...], 4
# (4 = selected)

options_for_select [['Lisbon',1], ['Madrid',2], ...], 4
# Just makes <option> tags

Collections

f.collection_radio_buttons :author_id, Author.all, :id, :name_with_initial
f.collection_select :city_id, City.all, :id, :name
# (field, collection, value_key, label_key)

Time select

f.time_zone_select :time_zone
f.date_select :birthday

I18n

helpers:
  submit:
    # helpers.submit.<action>
    create: "Create a %{model}"
    update: "Confirm changes to %{model}"

    # helpers.submit.<model>.<action>
    article:
      create: "Publish article"
      update: "Update article"

  # helpers.label.<model>.<field>
  label:
    post:
      body: "Your body text"

Outside f

radio_button("post", "category", "rails")
radio_button("post", "category", "java")

# picks from @post.category
# <input type="radio" id="post_category_rails" name="post[category]"
#  value="rails" checked="checked" />

Reference

select(method, choices = nil, options = {}, html_options = {}, &block)
  choices == [ ['label', id], ... ]

submit(value=nil, options={})