title: linq query for no match rows
body: <p>I would like to know how to do a query that returns rows that have NO match.</p>
  
  <p>For example: The query should return the list of people that have not rented any movies since a given date.</p>
  
  <p>I wrote this code but I was helped by a foreach sentence.</p>
  
  <p>Thanks in advance, micha.</p>
  
  <pre><code>// dt is a date from the user
  public IEnumerable inActiveRenters(DateTime dt)
      {
          var rents = from r in myDb.Rents
                      where r.RentStart &gt; dt
                      select r;
  
          List&lt;Member&gt; memberList = new List&lt;Member&gt;();
  
          foreach (Member m in myDb.Members)
          {
              bool notRent = true;
              foreach (Rent r in rents)
              {
                  if (r.MemberID == m.MemberID)
                  {
                      notRent = false;
                  }
              }
              if (notRent)
              {
                  memberList.Add(m);
              }
          }
  
          var list = from m in memberList
                     select new { m.MemberID, m.FirstName };
  
          return list;
      }
  </code></pre>