title: Error: "Only primitive types or enumeration types are supported in this context"
body: <p>Looked through related posts but still having difficulty.  Here is my code:</p>
  
  <pre><code>var id = Request.QueryString["id"].AsInt();
  var accountNum = Request.QueryString["accountnum"];
  
  var orderIDs = new List&lt;OrderID&gt;();
  
  // Order IDs are in the form: OrderNum-OrderLine[,...]
  // e.g. orderids=41417-6,36703-1
  
  foreach (var orderID in Request.QueryString["orderids"].Split(',')) {
      var components = orderID.Split('-');
      orderIDs.Add(new OrderID() {
          OrderNum = components[0].AsInt(), 
          OrderLine = components[1].AsInt()
      });
  }
  
  var dbContext = new TelecomEntities();
  var assignedLines = dbContext.LineAssignments
      .Where(a =&gt; orderIDs
          .Any(i =&gt; a.OrderNum == i.OrderNum &amp;&amp; a.OrderLine == i.OrderLine))
      .ToList();
  </code></pre>
  
  <p>When running this, I get the error: <em>Unable to create a constant value of type 'OrderID'. Only primitive types or enumeration types are supported in this context.</em></p>
  
  <p>From what I've read in other posts, I can't perform the query because <code>orderIDs</code> is not in the <code>dbContent</code> context.</p>
  
  <p><strong>Edit:</strong> OrderID Class</p>
  
  <pre><code>public class OrderID
  {
      public int OrderNum { get; set; }
      public int OrderLine { get; set; }
  
      public OrderID() { }
  }
  </code></pre>