how to update a single contact's group membership with Google Contact API and .NET?

Question

I want to retrieve a specific contact, and update its group membership. I already know the self link of the contact. To get the specific contact, the developer's guide says to do this:

//The example assumes the ContactRequest object (cr) is already set up.

Contact c = cr.Retrieve<Contact>("http://www.google.com/m8/feeds/contacts/liz%40gmail.com/full/12345");

but when I compile this, I get an error:

Argument 1: cannot convert from 'string' to 'Google.Contacts.Contact'

If I change it to:

Contact c = cr.Retrieve<Contact>(new Uri("http://www.google.com/m8/feeds/contacts/liz%40gmail.com/full/12345"));

then it compiles, and seems to retrieve okay, but I'm unable to update the contact's group membership:

c.GroupMembership.Add(member2);
cr.Update(c);

as the cr.Update(c) line throws a GDataRequestException (400 Bad Request) with a response string of:

"Group membership information not supported"

What am I doing wrong?

Thanks,

Mark

Beiley Software

Answer 1

I figured out what I was doing wrong... When retrieving the contact, I was using the "Id" property, instead of the "Self" property. The "Id" property has "base" projection, while the "Self" property has "Full" projection. Once I switched to using "Self" it worked properly.

Mark