title: Combine data gathered from different sources into one IEnumerable object
body: <p>I have this method below that gathers data from different sources and returns it as one IEnumerable. </p>
  
  <p>I'm having trouble though, figuring out how to combine all the sources into one object of type TotalRoomContents.</p>
  
  <p>TotalRoomContents is of type <code>IEnumerable&lt;String&gt;</code>.</p>
  
  <p>Here is the unfinished method:</p>
  
  <pre><code>    public static TotalRoomContents GetRoomContents(this Dungeon dungeon)
      {
          var customArmor = dungeon.Rooms
                      .Select(pe =&gt; pe.Room)
                      .Where(e =&gt; e.Monster.IsActive);
              // check each customArmor object to see if it exists in the MapLookupByRoomId dictionary
              if (customArmor != null &amp;&amp; MapLookupByRoomId.ContainsKey(customArmor.Id))
                  // add all item(s) of type customArmor to TotalRoomContents()
  
              if(dungeon.RoomType?.InventoryContent != null)
              {
                      // add item(s) from dungeon.RoomType?.InventoryContent to TotalRoomContents()
              }
  
              return new TotalRoomContents()
      }
  </code></pre>
  
  <p>As you can see, I don't know how to add the item(s) to the <code>TotalRoomContents</code> object.</p>
  
  <p>The items will be from <code>dungeon.RoomType?.InventoryContent</code> and all the <code>customArmor</code> objects found in the linq query.</p>
  
  <p>Is there a way to do this in one method or do I need to create some type of other method to do this?</p>
  
  <p>Thanks!</p>