title: Parallel foreach ConcurrentDictionary<string, string> add
body: <p>I have entries like in a phone book: name + address.
  The source is on a web site, the count is over 1K records.</p>
  
  <p>Question is:</p>
  
  <p><strong>How do i use/implement</strong> <code>ConcurrentDictionary</code> with <code>ParallelForeach</code><strong>?</strong></p>
  
  <p>I might as well ask will it better perform: </p>
  
  <p><code>ConcurrentDictionary</code> &amp; <code>ParallelForeach</code> </p>
  
  <p>vs </p>
  
  <p><code>Dictionary</code> &amp; <code>foreach</code> </p>
  
  <p>As the name <strong>is not allowed to have duplicates</strong> being the key, and i think i understood correctly that <code>ConcurrentDictionary</code> has its own built-in function to add(<code>TryAdd</code>) only if key does not exists.
  so the issue of not allowing adding duplicated keys already taken cared of, so from that point i could clearly see the balance is turning towards <code>ConcurrentDictionary</code> rather than standard-sequential <code>Dictionary</code> </p>
  
  <p>So how do I add name &amp; address from any given data source and load it via  Parallelforeach into a ConcurrentDictionary </p>