title: Duplicate keys in .NET dictionaries?
body: <p>Are there any dictionary classes in the .NET base class library which allow duplicate keys to be used?  The only solution I've found is to create, for example, a class like:</p>
  
  <pre><code>Dictionary&lt;string, List&lt;object&gt;&gt;
  </code></pre>
  
  <p>But this is quite irritating to actually use.  In Java, I believe a MultiMap accomplishes this, but cannot find an analog in .NET.</p>