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diff --git a/guides/source/getting_started.textile b/guides/source/getting_started.textile index 73f85ab8f9..478aa74f27 100644 --- a/guides/source/getting_started.textile +++ b/guides/source/getting_started.textile @@ -726,7 +726,7 @@ something went wrong. To do that, you'll modify +app/views/posts/index.html.erb+ to check for error messages: <erb> -<%= form_for :post do |f| %> +<%= form_for :post, :url => { :action => :create } do |f| %> <% if @post.errors.any? %> <div id="errorExplanation"> <h2><%= pluralize(@post.errors.count, "error") %> prohibited @@ -776,6 +776,136 @@ Now you'll get a nice error message when saving a post without title: !images/getting_started/form_with_errors.png(Form With Errors)! +h4. Updating Posts + +We've covered the "CR" part of CRUD. Now let's focus on the "U" part, +updating posts. + +The first step we'll take is adding a +edit+ action to ++posts_controller+. + +Start by adding a route to +config/routes.rb+: + +<ruby> +get "posts/:id/edit" => "posts#edit" +</ruby> + +And then add the controller action: + +<ruby> +def edit + @post = Post.find(params[:id]) +end +</ruby> + +The view will contain a form similar to the one we used when creating +new posts. Create a file called +app/views/posts/edit.html.erb+ and make +it look as follows: + +<erb> +<h1>Editing post</h1> + +<%= form_for :post, :url => { :action => :update, :id => @post.id }, +:method => :put do |f| %> + <% if @post.errors.any? %> + <div id="errorExplanation"> + <h2><%= pluralize(@post.errors.count, "error") %> prohibited + this post from being saved:</h2> + <ul> + <% @post.errors.full_messages.each do |msg| %> + <li><%= msg %></li> + <% end %> + </ul> + </div> + <% end %> + <p> + <%= f.label :title %><br> + <%= f.text_field :title %> + </p> + + <p> + <%= f.label :text %><br> + <%= f.text_area :text %> + </p> + + <p> + <%= f.submit %> + </p> +<% end %> + +<%= link_to 'Back', :action => :index %> +</erb> + +This time we point the form to the +update+ action (not defined yet). +The +:method => :put+ option tells Rails that we want this form to be +submitted via +put+, which is the http method you're expected to use to +*update* resources according to the REST protocol. + +TIP: By default forms built with the +form_for_ helper are sent via +POST+. + +Moving on, we need to add the +update+ action. The file ++config/routes.rb+ will need just one more line: + +<ruby> +put "posts/:id/update" +</ruby> + +And the +update+ action in +posts_controller+ itself should not look too complicated by now: + +<ruby> +def update + @post = Post.find(params[:id]) + + if @post.update_attributes(params[:post]) + redirect_to :action => :show, :id => @post.id + else + render 'edit' + end +end +</ruby> + +The new method +update_attributes+ is used when you want to update a record +that already exists, and it accepts an hash containing the attributes +that you want to update. As before, if there was an error updating the +post we want to show the form back to the user. + +TIP: you don't need to pass all attributes to +update_attributes+. For +example, if you'd call +@post.update_attributes(:title => 'A new title') +Rails would only update the +title+ attribute, leaving all other +attributes untouched. + +Finally, we want to show a link to the +edit+ action in the +index+ and ++show+ views: + +<erb> +# app/view/posts/index.html.erb + +<table> + <tr> + <th>Title</th> + <th>Text</th> + <th></th> + <th></th> + </tr> + +<% @posts.each do |post| %> + <tr> + <td><%= post.title %></td> + <td><%= post.text %></td> + <td><%= link_to 'Show', :action => :show, :id => post.id %></td> + <td><%= link_to 'Edit', :action => :edit, :id => post.id %></td> + </tr> +<% end %> +</table> + +# app/view/posts/show.html.erb + +... + +<%= link_to 'Back', :action => :index %> +| <%= link_to 'Edit', :action => :edit, :id => @post.id %> +</erb> + h4. Using the Console To see your validations in action, you can use the console. The console is a |