title: using html.begin form, how to do add the value of {id} to the post url?
body: <p>i need to post url to be /controller/action/someID</p>
  
  <p>not sure how to get someID in using the BeginForm helper.</p>
  
  <pre><code>html.beginform("controller", "action", formmethod.post)
  </code></pre>