Action View URL Helpers
Provides a set of methods for making links and getting URLs that depend on the routing subsystem (see ActionDispatch::Routing
). This allows you to use the same format for links in views and controllers.
Namespace
Module
Methods
- button_to
- current_page?
- link_to
- link_to_if
- link_to_unless
- link_to_unless_current
- mail_to
- phone_to
- sms_to
Included Modules
Constants
BUTTON_TAG_METHOD_VERBS | = | %w{patch put delete} |
This helper may be included in any class that includes the URL helpers of a routes (routes.url_helpers). Some methods provided here will only work in the context of a request ( |
||
STRINGIFIED_COMMON_METHODS | = | { get: "get", delete: "delete", patch: "patch", post: "post", put: "put", }.freeze |
Instance Public methods
button_to(name = nil, options = nil, html_options = nil, &block)
Generates a form containing a single button that submits to the URL created by the set of options
. This is the safest method to ensure links that cause changes to your data are not triggered by search bots or accelerators.
You can control the form and button behavior with html_options
. Most values in html_options
are passed through to the button element. For example, passing a :class
option within html_options
will set the class attribute of the button element.
The class attribute of the form element can be set by passing a :form_class
option within html_options
. It defaults to "button_to"
to allow styling of the form and its children.
The form submits a POST request by default if the object is not persisted; conversely, if the object is persisted, it will submit a PATCH request. To specify a different HTTP verb use the :method
option within html_options
.
If the HTML button generated from button_to
does not work with your layout, you can consider using the link_to
method with the data-turbo-method
attribute as described in the link_to
documentation.
Options
The options
hash accepts the same options as url_for
. To generate a <form>
element without an [action]
attribute, pass false
:
<%= button_to "New", false %>
# => "<form method="post" class="button_to">
# <button type="submit">New</button>
# <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6"/>
# </form>"
Most values in html_options
are passed through to the button element, but there are a few special options:
-
:method
- Symbol of HTTP verb. Supported verbs are:post
,:get
,:delete
,:patch
, and:put
. By default it will be:post
. -
:disabled
- If set to true, it will generate a disabled button. -
:data
- This option can be used to add custom data attributes. -
:form
- This hash will be form attributes -
:form_class
- This controls the class of the form within which the submit button will be placed -
:params
- Hash of parameters to be rendered as hidden fields within the form.
Examples
<%= button_to "New", action: "new" %>
# => "<form method="post" action="/controller/new" class="button_to">
# <button type="submit">New</button>
# <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6" autocomplete="off"/>
# </form>"
<%= button_to "New", new_article_path %>
# => "<form method="post" action="/articles/new" class="button_to">
# <button type="submit">New</button>
# <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6" autocomplete="off"/>
# </form>"
<%= button_to "New", new_article_path, params: { time: Time.now } %>
# => "<form method="post" action="/articles/new" class="button_to">
# <button type="submit">New</button>
# <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6"/>
# <input type="hidden" name="time" value="2021-04-08 14:06:09 -0500" autocomplete="off">
# </form>"
<%= button_to [:make_happy, @user] do %>
Make happy <strong><%= @user.name %></strong>
<% end %>
# => "<form method="post" action="/users/1/make_happy" class="button_to">
# <button type="submit">
# Make happy <strong><%= @user.name %></strong>
# </button>
# <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6" autocomplete="off"/>
# </form>"
<%= button_to "New", { action: "new" }, form_class: "new-thing" %>
# => "<form method="post" action="/controller/new" class="new-thing">
# <button type="submit">New</button>
# <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6" autocomplete="off"/>
# </form>"
<%= button_to "Create", { action: "create" }, form: { "data-type" => "json" } %>
# => "<form method="post" action="/images/create" class="button_to" data-type="json">
# <button type="submit">Create</button>
# <input name="authenticity_token" type="hidden" value="10f2163b45388899ad4d5ae948988266befcb6c3d1b2451cf657a0c293d605a6" autocomplete="off"/>
# </form>"
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 296
def button_to(name = nil, options = nil, html_options = nil, &block)
html_options, options = options, name if block_given?
html_options ||= {}
html_options = html_options.stringify_keys
url =
case options
when FalseClass then nil
else url_for(options)
end
remote = html_options.delete("remote")
params = html_options.delete("params")
authenticity_token = html_options.delete("authenticity_token")
method = (html_options.delete("method").presence || method_for_options(options)).to_s
method_tag = BUTTON_TAG_METHOD_VERBS.include?(method) ? method_tag(method) : "".html_safe
form_method = method == "get" ? "get" : "post"
form_options = html_options.delete("form") || {}
form_options[:class] ||= html_options.delete("form_class") || "button_to"
form_options[:method] = form_method
form_options[:action] = url
form_options[:'data-remote'] = true if remote
request_token_tag = if form_method == "post"
request_method = method.empty? ? "post" : method
token_tag(authenticity_token, form_options: { action: url, method: request_method })
else
""
end
html_options = convert_options_to_data_attributes(options, html_options)
html_options["type"] = "submit"
button = if block_given?
content_tag("button", html_options, &block)
elsif button_to_generates_button_tag
content_tag("button", name || url, html_options, &block)
else
html_options["value"] = name || url
tag("input", html_options)
end
inner_tags = method_tag.safe_concat(button).safe_concat(request_token_tag)
if params
to_form_params(params).each do |param|
inner_tags.safe_concat tag(:input, type: "hidden", name: param[:name], value: param[:value],
autocomplete: "off")
end
end
html = content_tag("form", inner_tags, form_options)
prevent_content_exfiltration(html)
end
🔎 See on GitHub
current_page?(options = nil, check_parameters: false, **options_as_kwargs)
True if the current request URI was generated by the given options
.
Examples
Let’s say we’re in the http://www.example.com/shop/checkout?order=desc&page=1
action.
current_page?(action: 'process')
# => false
current_page?(action: 'checkout')
# => true
current_page?(controller: 'library', action: 'checkout')
# => false
current_page?(controller: 'shop', action: 'checkout')
# => true
current_page?(controller: 'shop', action: 'checkout', order: 'asc')
# => false
current_page?(controller: 'shop', action: 'checkout', order: 'desc', page: '1')
# => true
current_page?(controller: 'shop', action: 'checkout', order: 'desc', page: '2')
# => false
current_page?('http://www.example.com/shop/checkout')
# => true
current_page?('http://www.example.com/shop/checkout', check_parameters: true)
# => false
current_page?('/shop/checkout')
# => true
current_page?('http://www.example.com/shop/checkout?order=desc&page=1')
# => true
Let’s say we’re in the http://www.example.com/products
action with method POST in case of invalid product.
current_page?(controller: 'product', action: 'index')
# => false
We can also pass in the symbol arguments instead of strings.
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 548
def current_page?(options = nil, check_parameters: false, **options_as_kwargs)
unless request
raise "You cannot use helpers that need to determine the current " \
"page unless your view context provides a Request object " \
"in a #request method"
end
return false unless request.get? || request.head?
options ||= options_as_kwargs
check_parameters ||= options.is_a?(Hash) && options.delete(:check_parameters)
url_string = URI::RFC2396_PARSER.unescape(url_for(options)).force_encoding(Encoding::BINARY)
# We ignore any extra parameters in the request_uri if the
# submitted URL doesn't have any either. This lets the function
# work with things like ?order=asc
# the behavior can be disabled with check_parameters: true
request_uri = url_string.index("?") || check_parameters ? request.fullpath : request.path
request_uri = URI::RFC2396_PARSER.unescape(request_uri).force_encoding(Encoding::BINARY)
if %r{^\w+://}.match?(url_string)
request_uri = +"#{request.protocol}#{request.host_with_port}#{request_uri}"
end
remove_trailing_slash!(url_string)
remove_trailing_slash!(request_uri)
url_string == request_uri
end
🔎 See on GitHub
link_to(name = nil, options = nil, html_options = nil, &block)
Creates an anchor element of the given name
using a URL created by the set of options
. See the valid options in the documentation for url_for
. It’s also possible to pass a String instead of an options hash, which generates an anchor element that uses the value of the String as the href for the link. Using a :back
Symbol instead of an options hash will generate a link to the referrer (a JavaScript back link will be used in place of a referrer if none exists). If nil
is passed as the name the value of the link itself will become the name.
Signatures
link_to(body, url, html_options = {})
# url is a String; you can use URL helpers like
# posts_path
link_to(body, url_options = {}, html_options = {})
# url_options, except :method, is passed to url_for
link_to(options = {}, html_options = {}) do
# name
end
link_to(url, html_options = {}) do
# name
end
link_to(active_record_model)
Options
-
:data
- This option can be used to add custom data attributes.
Examples
Because it relies on url_for
, link_to
supports both older-style controller/action/id arguments and newer RESTful routes. Current Rails style favors RESTful routes whenever possible, so base your application on resources and use
link_to "Profile", profile_path(@profile)
# => <a href="/profiles/1">Profile</a>
or the even pithier
link_to "Profile", @profile
# => <a href="/profiles/1">Profile</a>
in place of the older more verbose, non-resource-oriented
link_to "Profile", controller: "profiles", action: "show", id: @profile
# => <a href="/profiles/show/1">Profile</a>
Similarly,
link_to "Profiles", profiles_path
# => <a href="/profiles">Profiles</a>
is better than
link_to "Profiles", controller: "profiles"
# => <a href="/profiles">Profiles</a>
When name is nil
the href is presented instead
link_to nil, "http://example.com"
# => <a href="http://www.example.com">http://www.example.com</a>
More concise yet, when name
is an Active Record model that defines a to_s
method returning a default value or a model instance attribute
link_to @profile
# => <a href="http://www.example.com/profiles/1">Eileen</a>
You can use a block as well if your link target is hard to fit into the name parameter. ERB
example:
<%= link_to(@profile) do %>
<strong><%= @profile.name %></strong> -- <span>Check it out!</span>
<% end %>
# => <a href="/profiles/1">
<strong>David</strong> -- <span>Check it out!</span>
</a>
Classes and ids for CSS are easy to produce:
link_to "Articles", articles_path, id: "news", class: "article"
# => <a href="/articles" class="article" id="news">Articles</a>
Be careful when using the older argument style, as an extra literal hash is needed:
link_to "Articles", { controller: "articles" }, id: "news", class: "article"
# => <a href="/articles" class="article" id="news">Articles</a>
Leaving the hash off gives the wrong link:
link_to "WRONG!", controller: "articles", id: "news", class: "article"
# => <a href="/articles/index/news?class=article">WRONG!</a>
link_to
can also produce links with anchors or query strings:
link_to "Comment wall", profile_path(@profile, anchor: "wall")
# => <a href="/profiles/1#wall">Comment wall</a>
link_to "Ruby on Rails search", controller: "searches", query: "ruby on rails"
# => <a href="/searches?query=ruby+on+rails">Ruby on Rails search</a>
link_to "Nonsense search", searches_path(foo: "bar", baz: "quux")
# => <a href="/searches?foo=bar&baz=quux">Nonsense search</a>
You can set any link attributes such as target
, rel
, type
:
link_to "External link", "http://www.rubyonrails.org/", target: "_blank", rel: "nofollow"
# => <a href="http://www.rubyonrails.org/" target="_blank" rel="nofollow">External link</a>
Turbo
Rails
7 ships with Turbo enabled by default. Turbo provides the following :data
options:
-
turbo_method: symbol of HTTP verb
- Performs a Turbo link visit with the given HTTP verb. Forms are recommended when performing non-GET
requests. Only usedata-turbo-method
where a form is not possible. -
turbo_confirm: "question?"
- Adds a confirmation dialog to the link with the given value.
Consult the Turbo Handbook for more information on the options above.
Examples
link_to "Delete profile", @profile, data: { turbo_method: :delete }
# => <a href="/profiles/1" data-turbo-method="delete">Delete profile</a>
link_to "Visit Other Site", "https://rubyonrails.org/", data: { turbo_confirm: "Are you sure?" }
# => <a href="https://rubyonrails.org/" data-turbo-confirm="Are you sure?">Visit Other Site</a>
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 198
def link_to(name = nil, options = nil, html_options = nil, &block)
html_options, options, name = options, name, block if block_given?
options ||= {}
html_options = convert_options_to_data_attributes(options, html_options)
url = url_target(name, options)
html_options["href"] ||= url
content_tag("a", name || url, html_options, &block)
end
🔎 See on GitHub
link_to_if(condition, name, options = {}, html_options = {}, &block)
Creates a link tag of the given name
using a URL created by the set of options
if condition
is true, otherwise only the name is returned. To specialize the default behavior, you can pass a block that accepts the name or the full argument list for link_to_if
.
Examples
<%= link_to_if(@current_user.nil?, "Login", { controller: "sessions", action: "new" }) %>
# If the user isn't logged in...
# => <a href="/sessions/new/">Login</a>
<%=
link_to_if(@current_user.nil?, "Login", { controller: "sessions", action: "new" }) do
link_to(@current_user.login, { controller: "accounts", action: "show", id: @current_user })
end
%>
# If the user isn't logged in...
# => <a href="/sessions/new/">Login</a>
# If they are logged in...
# => <a href="/accounts/show/3">my_username</a>
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 437
def link_to_if(condition, name, options = {}, html_options = {}, &block)
if condition
link_to(name, options, html_options)
else
if block_given?
block.arity <= 1 ? capture(name, &block) : capture(name, options, html_options, &block)
else
ERB::Util.html_escape(name)
end
end
end
🔎 See on GitHub
link_to_unless(condition, name, options = {}, html_options = {}, &block)
Creates a link tag of the given name
using a URL created by the set of options
unless condition
is true, in which case only the name is returned. To specialize the default behavior (i.e., show a login link rather than just the plaintext link text), you can pass a block that accepts the name or the full argument list for link_to_unless
.
Examples
<%= link_to_unless(@current_user.nil?, "Reply", { action: "reply" }) %>
# If the user is logged in...
# => <a href="/controller/reply/">Reply</a>
<%=
link_to_unless(@current_user.nil?, "Reply", { action: "reply" }) do |name|
link_to(name, { controller: "accounts", action: "signup" })
end
%>
# If the user is logged in...
# => <a href="/controller/reply/">Reply</a>
# If not...
# => <a href="/accounts/signup">Reply</a>
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 414
def link_to_unless(condition, name, options = {}, html_options = {}, &block)
link_to_if !condition, name, options, html_options, &block
end
🔎 See on GitHub
link_to_unless_current(name, options = {}, html_options = {}, &block)
Creates a link tag of the given name
using a URL created by the set of options
unless the current request URI is the same as the links, in which case only the name is returned (or the given block is yielded, if one exists). You can give link_to_unless_current
a block which will specialize the default behavior (e.g., show a “Start Here” link rather than the link’s text).
Examples
Let’s say you have a navigation menu…
<ul id="navbar">
<li><%= link_to_unless_current("Home", { action: "index" }) %></li>
<li><%= link_to_unless_current("About Us", { action: "about" }) %></li>
</ul>
If in the “about” action, it will render…
<ul id="navbar">
<li><a href="/controller/index">Home</a></li>
<li>About Us</li>
</ul>
…but if in the “index” action, it will render:
<ul id="navbar">
<li>Home</li>
<li><a href="/controller/about">About Us</a></li>
</ul>
The implicit block given to link_to_unless_current
is evaluated if the current action is the action given. So, if we had a comments page and wanted to render a “Go Back” link instead of a link to the comments page, we could do something like this…
<%=
link_to_unless_current("Comment", { controller: "comments", action: "new" }) do
link_to("Go back", { controller: "posts", action: "index" })
end
%>
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 390
def link_to_unless_current(name, options = {}, html_options = {}, &block)
link_to_unless current_page?(options), name, options, html_options, &block
end
🔎 See on GitHub
mail_to(email_address, name = nil, html_options = {}, &block)
Creates a mailto link tag to the specified email_address
, which is also used as the name of the link unless name
is specified. Additional HTML attributes for the link can be passed in html_options
.
mail_to
has several methods for customizing the email itself by passing special keys to html_options
.
Options
-
:subject
- Preset the subject line of the email. -
:body
- Preset the body of the email. -
:cc
- Carbon Copy additional recipients on the email. -
:bcc
- Blind Carbon Copy additional recipients on the email. -
:reply_to
- Preset theReply-To
field of the email.
Obfuscation
Prior to Rails 4.0, mail_to
provided options for encoding the address in order to hinder email harvesters. To take advantage of these options, install the actionview-encoded_mail_to
gem.
Examples
mail_to "me@domain.com"
# => <a href="mailto:me@domain.com">me@domain.com</a>
mail_to "me@domain.com", "My email"
# => <a href="mailto:me@domain.com">My email</a>
mail_to "me@domain.com", cc: "ccaddress@domain.com",
subject: "This is an example email"
# => <a href="mailto:me@domain.com?cc=ccaddress@domain.com&subject=This%20is%20an%20example%20email">me@domain.com</a>
You can use a block as well if your link target is hard to fit into the name parameter. ERB
example:
<%= mail_to "me@domain.com" do %>
<strong>Email me:</strong> <span>me@domain.com</span>
<% end %>
# => <a href="mailto:me@domain.com">
<strong>Email me:</strong> <span>me@domain.com</span>
</a>
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 487
def mail_to(email_address, name = nil, html_options = {}, &block)
html_options, name = name, nil if name.is_a?(Hash)
html_options = (html_options || {}).stringify_keys
extras = %w{ cc bcc body subject reply_to }.map! { |item|
option = html_options.delete(item).presence || next
"#{item.dasherize}=#{ERB::Util.url_encode(option)}"
}.compact
extras = extras.empty? ? "" : "?" + extras.join("&")
encoded_email_address = ERB::Util.url_encode(email_address).gsub("%40", "@")
html_options["href"] = "mailto:#{encoded_email_address}#{extras}"
content_tag("a", name || email_address, html_options, &block)
end
🔎 See on GitHub
phone_to(phone_number, name = nil, html_options = {}, &block)
Creates a TEL anchor link tag to the specified phone_number
. When the link is clicked, the default app to make phone calls is opened and prepopulated with the phone number.
If name
is not specified, phone_number
will be used as the name of the link.
A country_code
option is supported, which prepends a plus sign and the given country code to the linked phone number. For example, country_code: "01"
will prepend +01
to the linked phone number.
Additional HTML attributes for the link can be passed via html_options
.
Options
-
:country_code
- Prepends the country code to the phone number
Examples
phone_to "1234567890"
# => <a href="tel:1234567890">1234567890</a>
phone_to "1234567890", "Phone me"
# => <a href="tel:1234567890">Phone me</a>
phone_to "1234567890", country_code: "01"
# => <a href="tel:+011234567890">1234567890</a>
You can use a block as well if your link target is hard to fit into the name parameter. ERB example:
<%= phone_to "1234567890" do %>
<strong>Phone me:</strong>
<% end %>
# => <a href="tel:1234567890">
<strong>Phone me:</strong>
</a>
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 669
def phone_to(phone_number, name = nil, html_options = {}, &block)
html_options, name = name, nil if name.is_a?(Hash)
html_options = (html_options || {}).stringify_keys
country_code = html_options.delete("country_code").presence
country_code = country_code.nil? ? "" : "+#{ERB::Util.url_encode(country_code)}"
encoded_phone_number = ERB::Util.url_encode(phone_number)
html_options["href"] = "tel:#{country_code}#{encoded_phone_number}"
content_tag("a", name || phone_number, html_options, &block)
end
🔎 See on GitHub
sms_to(phone_number, name = nil, html_options = {}, &block)
Creates an SMS anchor link tag to the specified phone_number
. When the link is clicked, the default SMS messaging app is opened ready to send a message to the linked phone number. If the body
option is specified, the contents of the message will be preset to body
.
If name
is not specified, phone_number
will be used as the name of the link.
A country_code
option is supported, which prepends a plus sign and the given country code to the linked phone number. For example, country_code: "01"
will prepend +01
to the linked phone number.
Additional HTML attributes for the link can be passed via html_options
.
Options
-
:country_code
- Prepend the country code to the phone number. -
:body
- Preset the body of the message.
Examples
sms_to "5155555785"
# => <a href="sms:5155555785;">5155555785</a>
sms_to "5155555785", country_code: "01"
# => <a href="sms:+015155555785;">5155555785</a>
sms_to "5155555785", "Text me"
# => <a href="sms:5155555785;">Text me</a>
sms_to "5155555785", body: "I have a question about your product."
# => <a href="sms:5155555785;?body=I%20have%20a%20question%20about%20your%20product">5155555785</a>
You can use a block as well if your link target is hard to fit into the name parameter. ERB example:
<%= sms_to "5155555785" do %>
<strong>Text me:</strong>
<% end %>
# => <a href="sms:5155555785;">
<strong>Text me:</strong>
</a>
📝 Source code
# File actionview/lib/action_view/helpers/url_helper.rb, line 618
def sms_to(phone_number, name = nil, html_options = {}, &block)
html_options, name = name, nil if name.is_a?(Hash)
html_options = (html_options || {}).stringify_keys
country_code = html_options.delete("country_code").presence
country_code = country_code ? "+#{ERB::Util.url_encode(country_code)}" : ""
body = html_options.delete("body").presence
body = body ? "?&body=#{ERB::Util.url_encode(body)}" : ""
encoded_phone_number = ERB::Util.url_encode(phone_number)
html_options["href"] = "sms:#{country_code}#{encoded_phone_number};#{body}"
content_tag("a", name || phone_number, html_options, &block)
end
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