title: Parsing a JSON parameter
body: <p>I must be missing something obvious - but</p>
  
  <p>I have a controller.  One of the action recieves the following JSON parameter</p>
  
  <pre><code>Parameters: {"user_save_name"=&gt;{"evaluation_assumption_id"=&gt;"51"}, "id"=&gt;"1"}
  </code></pre>
  
  <p>I want to assign the value associated with the evaluation_assumption_id e.g. in this case 51</p>
  
  <p>Within the controller I can get the id parameter with the statement</p>
  
  <pre><code>@jsondata = params[:id]
  </code></pre>
  
  <p>which gives me 1</p>
  
  <p>If use the following statement within the controller </p>
  
  <pre><code>@jsondata = params[:user_save_name] 
  </code></pre>
  
  <p>I get {"evaluation_assumption_id"=>"51"} 
  What I can't do is assign the value 51 to a variable.   How do I do this ?<br>
  Thanks in advance 
  Pierre</p>