title: Loop through ICollection and set to null
body: <p>I need to remove the data from an ICollection if the ID of the collection is in a List of ID's.</p>
  
  <p>What I have so far:</p>
  
  <pre><code>    foreach (var notSelectedToolId in notSelectedToolIds)
      {
          for (int i = 0; i &lt; matchingHoleInfoVm.ToolHeader.Count; i++)
          {
              if (matchingHoleInfoVm.ToolHeader.ElementAt(i).ToolID == notSelectedToolId)
              {
                  matchingHoleInfoVm.ToolHeader.ElementAt(i) = new ToolHeaderViewModel();
              }
          }
      }
  </code></pre>
  
  <p>The error I get: <code>"This expression cannot be used as an assignment target"</code>.</p>
  
  <p>How can I make this work?</p>