title: Rails getting single values from request
body: <p>in Rails the create method in a Controller by default receives an HTTP request with different values.
  By default new records are created like this:</p>
  
  <pre><code>@apo = Apo.new(params[:apo])
  </code></pre>
  
  <p>But how can i access single Values from this params hash?</p>
  
  <p>I would like to create something like this:</p>
  
  <pre><code>@apo = Apo.new do |a|
          a.name = $someVariable
          a.value = $anotherVariable
          a.quantity = -&gt; here i want to have one value which is in params[:apo]
          end
  </code></pre>
  
  <p>Do you understand what i´m looking for?
  Tried million possibilities but it just doesn´t work.</p>
  
  <p>Alternatively, is it possible, to create a second params hash in the view, which only saves this one value?</p>
  
  <p>P.S. i don´t want to use JavaScript for doing this...</p>
  
  <p>Thanks a lot!</p>