title: How to get type of TKey and TValue given a Dictionary<TKey,TValue> type
body: <p>I want to get type of TKey and TValue given a <code>Dictionary&lt;TKey,TValue&gt;</code> type.</p>
  
  <p>eg. If type is <code>Dictionary&lt;Int32,String&gt;</code> I want to know how to get 
  keyType = typeof(Int32) and 
  valueType = typeof(String)</p>