Module | ActionView::Helpers::UrlHelper |
In: |
vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb
|
Provides a set of methods for making easy links and getting urls that depend on the controller and action. This means that you can use the same format for links in the views that you do in the controller. The different methods are even named synchronously, so link_to uses that same url as is generated by url_for, which again is the same url used for redirection in redirect_to.
Generates a form containing a sole button that submits to the URL given by options. Use this method instead of link_to for actions that do not have the safe HTTP GET semantics implied by using a hypertext link.
The parameters are the same as for link_to. Any html_options that you pass will be applied to the inner input element. In particular, pass
:disabled => true/false
as part of html_options to control whether the button is disabled. The generated form element is given the class ‘button-to’, to which you can attach CSS styles for display purposes.
Example 1:
# inside of controller for "feeds" button_to "Edit", :action => 'edit', :id => 3
Generates the following HTML (sans formatting):
<form method="post" action="/feeds/edit/3" class="button-to"> <div><input value="Edit" type="submit" /></div> </form>
Example 2:
button_to "Destroy", { :action => 'destroy', :id => 3 }, :confirm => "Are you sure?"
Generates the following HTML (sans formatting):
<form method="post" action="/feeds/destroy/3" class="button-to"> <div><input onclick="return confirm('Are you sure?');" value="Destroy" type="submit" /> </div> </form>
NOTE: This method generates HTML code that represents a form. Forms are "block" content, which means that you should not try to insert them into your HTML where only inline content is expected. For example, you can legally insert a form inside of a div or td element or in between p elements, but not in the middle of a run of text, nor can you place a form within another form. (Bottom line: Always validate your HTML before going public.)
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 110 110: def button_to(name, options = {}, html_options = nil) 111: html_options = (html_options || {}).stringify_keys 112: convert_boolean_attributes!(html_options, %w( disabled )) 113: 114: if confirm = html_options.delete("confirm") 115: html_options["onclick"] = "return #{confirm_javascript_function(confirm)};" 116: end 117: 118: url = options.is_a?(String) ? options : url_for(options) 119: name ||= url 120: 121: html_options.merge!("type" => "submit", "value" => name) 122: 123: "<form method=\"post\" action=\"#{h url}\" class=\"button-to\"><div>" + 124: tag("input", html_options) + "</div></form>" 125: end
This tag is deprecated. Combine the link_to and AssetTagHelper::image_tag yourself instead, like:
link_to(image_tag("rss", :size => "30x45", :border => 0), "http://www.example.com")
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 130 130: def link_image_to(src, options = {}, html_options = {}, *parameters_for_method_reference) 131: image_options = { "src" => src.include?("/") ? src : "/images/#{src}" } 132: image_options["src"] += ".png" unless image_options["src"].include?(".") 133: 134: html_options = html_options.stringify_keys 135: if html_options["alt"] 136: image_options["alt"] = html_options["alt"] 137: html_options.delete "alt" 138: else 139: image_options["alt"] = src.split("/").last.split(".").first.capitalize 140: end 141: 142: if html_options["size"] 143: image_options["width"], image_options["height"] = html_options["size"].split("x") 144: html_options.delete "size" 145: end 146: 147: if html_options["border"] 148: image_options["border"] = html_options["border"] 149: html_options.delete "border" 150: end 151: 152: if html_options["align"] 153: image_options["align"] = html_options["align"] 154: html_options.delete "align" 155: end 156: 157: link_to(tag("img", image_options), options, html_options, *parameters_for_method_reference) 158: end
Creates a link tag of the given name using an URL created by the set of options. See the valid options in the documentation for ActionController::Base#url_for. It‘s also possible to pass a string instead of an options hash to get a link tag that just points without consideration. If nil is passed as a name, the link itself will become the name.
The html_options has three special features. One for creating javascript confirm alerts where if you pass :confirm => ‘Are you sure?’, the link will be guarded with a JS popup asking that question. If the user accepts, the link is processed, otherwise not.
Another for creating a popup window, which is done by either passing :popup with true or the options of the window in Javascript form.
And a third for making the link do a POST request (instead of the regular GET) through a dynamically added form element that is instantly submitted. Note that if the user has turned off Javascript, the request will fall back on the GET. So its your responsibility to determine what the action should be once it arrives at the controller. The POST form is turned on by passing :post as true. Note, it‘s not possible to use POST requests and popup targets at the same time (an exception will be thrown).
Examples:
link_to "Delete this page", { :action => "destroy", :id => @page.id }, :confirm => "Are you sure?" link_to "Help", { :action => "help" }, :popup => true link_to "Busy loop", { :action => "busy" }, :popup => ['new_window', 'height=300,width=600'] link_to "Destroy account", { :action => "destroy" }, :confirm => "Are you sure?", :post => true
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 51 51: def link_to(name, options = {}, html_options = nil, *parameters_for_method_reference) 52: if html_options 53: html_options = html_options.stringify_keys 54: convert_options_to_javascript!(html_options) 55: tag_options = tag_options(html_options) 56: else 57: tag_options = nil 58: end 59: url = options.is_a?(String) ? options : self.url_for(options, *parameters_for_method_reference) 60: "<a href=\"#{url}\"#{tag_options}>#{name || url}</a>" 61: end
Create a link tag of the given name using an URL created by the set of options, if condition is true, in which case only the name is returned (or the given block is yielded, if one exists).
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 186 186: def link_to_if(condition, name, options = {}, html_options = {}, *parameters_for_method_reference, &block) 187: link_to_unless !condition, name, options, html_options, *parameters_for_method_reference, &block 188: end
Alias for link_image_to
Create a link tag of the given name using an URL created by the set of options, unless condition is true, in which case only the name is returned (or the given block is yielded, if one exists).
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 172 172: def link_to_unless(condition, name, options = {}, html_options = {}, *parameters_for_method_reference, &block) 173: if condition 174: if block_given? 175: block.arity <= 1 ? yield(name) : yield(name, options, html_options, *parameters_for_method_reference) 176: else 177: name 178: end 179: else 180: link_to(name, options, html_options, *parameters_for_method_reference) 181: end 182: end
Creates a link tag of the given name using an URL created by the set of options, unless the current request uri is the same as the link‘s, in which case only the name is returned (or the given block is yielded, if one exists). This is useful for creating link bars where you don‘t want to link to the page currently being viewed.
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 166 166: def link_to_unless_current(name, options = {}, html_options = {}, *parameters_for_method_reference, &block) 167: link_to_unless current_page?(options), name, options, html_options, *parameters_for_method_reference, &block 168: end
Creates a link tag for starting an email to the specified email_address, which is also used as the name of the link unless name is specified. Additional HTML options, such as class or id, can be passed in the html_options hash.
You can also make it difficult for spiders to harvest email address by obfuscating them. Examples:
mail_to "me@domain.com", "My email", :encode => "javascript" # => <script type="text/javascript" language="javascript">eval(unescape('%64%6f%63%75%6d%65%6e%74%2e%77%72%69%74%65%28%27%3c%61%20%68%72%65%66%3d%22%6d%61%69%6c%74%6f%3a%6d%65%40%64%6f%6d%61%69%6e%2e%63%6f%6d%22%3e%4d%79%20%65%6d%61%69%6c%3c%2f%61%3e%27%29%3b'))</script> mail_to "me@domain.com", "My email", :encode => "hex" # => <a href="mailto:%6d%65@%64%6f%6d%61%69%6e.%63%6f%6d">My email</a>
You can also specify the cc address, bcc address, subject, and body parts of the message header to create a complex e-mail using the corresponding cc, bcc, subject, and body html_options keys. Each of these options are URI escaped and then appended to the email_address before being output. Be aware that javascript keywords will not be escaped and may break this feature when encoding with javascript. Examples:
mail_to "me@domain.com", "My email", :cc => "ccaddress@domain.com", :bcc => "bccaddress@domain.com", :subject => "This is an example email", :body => "This is the body of the message." # => <a href="mailto:me@domain.com?cc="ccaddress@domain.com"&bcc="bccaddress@domain.com"&body="This%20is%20the%20body%20of%20the%20message."&subject="This%20is%20an%20example%20email">My email</a>
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 208 208: def mail_to(email_address, name = nil, html_options = {}) 209: html_options = html_options.stringify_keys 210: encode = html_options.delete("encode") 211: cc, bcc, subject, body = html_options.delete("cc"), html_options.delete("bcc"), html_options.delete("subject"), html_options.delete("body") 212: 213: string = '' 214: extras = '' 215: extras << "cc=#{CGI.escape(cc).gsub("+", "%20")}&" unless cc.nil? 216: extras << "bcc=#{CGI.escape(bcc).gsub("+", "%20")}&" unless bcc.nil? 217: extras << "body=#{CGI.escape(body).gsub("+", "%20")}&" unless body.nil? 218: extras << "subject=#{CGI.escape(subject).gsub("+", "%20")}&" unless subject.nil? 219: extras = "?" << extras.gsub!(/&?$/,"") unless extras.empty? 220: 221: email_address_obfuscated = email_address.dup 222: email_address_obfuscated.gsub!(/@/, html_options.delete("replace_at")) if html_options.has_key?("replace_at") 223: email_address_obfuscated.gsub!(/\./, html_options.delete("replace_dot")) if html_options.has_key?("replace_dot") 224: 225: if encode == 'javascript' 226: tmp = "document.write('#{content_tag("a", name || email_address, html_options.merge({ "href" => "mailto:"+email_address.to_s+extras }))}');" 227: for i in 0...tmp.length 228: string << sprintf("%%%x",tmp[i]) 229: end 230: "<script type=\"text/javascript\">eval(unescape('#{string}'))</script>" 231: elsif encode == 'hex' 232: for i in 0...email_address.length 233: if email_address[i,1] =~ /\w/ 234: string << sprintf("%%%x",email_address[i]) 235: else 236: string << email_address[i,1] 237: end 238: end 239: content_tag "a", name || email_address_obfuscated, html_options.merge({ "href" => "mailto:#{string}#{extras}" }) 240: else 241: content_tag "a", name || email_address_obfuscated, html_options.merge({ "href" => "mailto:#{email_address}#{extras}" }) 242: end 243: end
Returns the URL for the set of options provided. This takes the same options as url_for. For a list, see the documentation for ActionController::Base#url_for. Note that it‘ll set :only_path => true so you‘ll get /controller/action instead of the example.com/controller/action part (makes it harder to parse httpd log files)
When called from a view, url_for returns an HTML escaped url. If you need an unescaped url, pass :escape => false to url_for.
# File vendor/rails/actionpack/lib/action_view/helpers/url_helper.rb, line 20 20: def url_for(options = {}, *parameters_for_method_reference) 21: if options.kind_of? Hash 22: options = { :only_path => true }.update(options.symbolize_keys) 23: escape = options.key?(:escape) ? options.delete(:escape) : true 24: else 25: escape = true 26: end 27: url = @controller.send(:url_for, options, *parameters_for_method_reference) 28: escape ? html_escape(url) : url 29: end