Question

So when one generates scaffodl, the controller automatically creates these blocks(?) like this

respond_to do |format|
      format.html
      format.xml  { render :xml => @c }
    end

what does this really do and how come it has format.html and format.xml? What does each do?

Answer 1

It defines that the current action will respond to various formats (the action’s content can be rendered in many ways, not only plain old HTML).

• If you open your browser and type /my/path/to/action.html, it will render HTML (from the template);
• If you type /my/path/to/action.xml, it will render XML using { render :xml => @c }. XML will be generated by Rails by calling the to_xml method on the @c variable;
• However, if you point to /my/path/to/action.json, it will throw a 404 error.