title: Which C# data types are not WCF serializable?
body: <p>We have C# entity classes which map to some of our SQL Server database tables. We need to be able to serialize these classes in order to send them back to the client, from the server, via WCF. For each SQL Server data type, we have a corresponding C# CLR data type in the associated entity. </p>
  
  <p>We have some SQL Server data types, such as Image and VarBinary that we need to map to a C# CLR data type, so we can pass the data back to the client. The problem is that I'm not sure what CLR data type to use for these Image and VarBinary SQL types, so that we can serialize them via WCF.</p>
  
  <p>Thanks.</p>