DevForce Community Forum : 'System.Reflection.RuntimeMethodInfo' cannot be serialized

'System.Reflection.RuntimeMethodInfo' cannot be serialized : Aha!We found it. Our client-side...

Fri, 19 Mar 2010 13:22:28 -700

Author: ahopper
Subject: 1692
Posted: 19-Mar-2010 at 1:22pm

Aha! We found it. Our client-side app.config did not have the clientApplicationType attribute set to �Silverlight� and this appears to break the code that serializes the Where clause.

'System.Reflection.RuntimeMethodInfo' cannot be serialized : Hi, Ting! Yes, these are EF classes,...

Thu, 18 Mar 2010 15:29:37 -700

Author: ahopper
Subject: 1692
Posted: 18-Mar-2010 at 3:29pm

Hi, Ting! Yes, these are EF classes, and DisplayName is bound to a database field. To what address should I send the edmx file?

'System.Reflection.RuntimeMethodInfo' cannot be serialized : Hi Andy, A) If Principal isa...

Thu, 18 Mar 2010 12:53:46 -700

Author: ting
Subject: 1692
Posted: 18-Mar-2010 at 12:53pm

Hi Andy,

A) If Principal is a POCO class you should do these things:

Mark the class with the [DiscoverableType(DiscoverableTypeMode.KnownType)] attribute or have the class implement IKnownType (a marker interface).
Mark each property with the [DataMember] attribute.

For example:

[DiscoverableType(DiscoverableTypeMode.KnownType)]

public class Principal {

...

[DataMember]

public String DisplayName {

get { ... }

set { ... }

}

...

}

B) If Principal is a standard DevForce Entity, you can only issue queries to the database on properties that are backed by database columns. If DisplayName is a calculated or custom property, the database engine doesn't know what to do with it. Once you have brought down the object into the client-side cache, however, you can use LINQ-to-objects to query on any arbitrary property.

If you're still having problems, send us the edmx file and we'll have a look.

Good luck!

'System.Reflection.RuntimeMethodInfo' cannot be serialized : We are trying to use the fluent...

Thu, 18 Mar 2010 09:22:47 -700

Author: ahopper
Subject: 1692
Posted: 18-Mar-2010 at 9:22am

We are trying to use the fluent interface to generate a Linq query that applies a where clause:

em.ExecuteQueryAsync<Principal>(em.Principals.Where(p => p.DisplayName == "ahopper"), this.QueryExecuted, null);

However, when the callback is invoked, it has an error:

�Type 'System.Reflection.RuntimeMethodInfo' cannot be serialized. Consider marking it with the DataContractAttribute attribute, and marking all of its members you want serialized with the DataMemberAttribute attribute. Alternatively, you can ensure that the type is public and has a parameterless constructor - all public members of the type will then be serialized, and no attributes will be required.�

Are we simply using the API incorrectly?

Many thanks!

Andy Hopper

Enterprise Architect, Wintellect

ahopper@wintellect.com