title: Multiple WHERE Clauses with LINQ extension methods
body: <p>I have a LINQ query that looks like the following:</p>
  
  <pre><code>DateTime today = DateTime.UtcNow;
  var results = from order in context.Orders
                where ((order.OrderDate &lt;= today) &amp;&amp; (today &lt;= order.OrderDate))
                select order;
  </code></pre>
  
  <p>I am trying to learn / understand LINQ. In some cases, I need to add two additional WHERE clauses. In an effort to do this, I'm using:</p>
  
  <pre><code>if (useAdditionalClauses)
  {
    results = results.Where(o =&gt; o.OrderStatus == OrderStatus.Open)  // Now I'm stuck.
  }
  </code></pre>
  
  <p>As you can see, I know how to add an additional WHERE clause. But how do I add multiple? For instance, I'd like to add </p>
  
  <p><code>WHERE o.OrderStatus == OrderStatus.Open AND o.CustomerID == customerID</code></p>
  
  <p>to my previous query. How do I do this using extension methods?</p>
  
  <p>Thank you!</p>