Client Object Model RoleDefinitionBindingCollection.Remove not working

Question

I'm using the Client Object Model and trying to remove a specific RoleDefinition from a RoleDefinitionBindingCollection in a RoleAssignment.

This is the code I'm using:

        Web web = context.Web;
        List list = context.Web.Lists.GetByTitle("List");
        context.Load(
            list,
            l => l.RoleAssignments.Include(
                ra => ra.Member,
                ra => ra.RoleDefinitionBindings
                )
            );

        context.ExecuteQuery();

        List<RoleDefinition> toDelete = new List<RoleDefinition>();

        foreach (RoleAssignment ra in list.RoleAssignments) {
            toDelete.Clear();

            foreach (RoleDefinition rd in ra.RoleDefinitionBindings) {
                if (rd.RoleTypeKind == RoleType.Administrator) {
                    toDelete.Add(rd);                        
                }
            }

            if (toDelete.Count > 0) {
                toDelete.ForEach(td => ra.RoleDefinitionBindings.Remove(td));
            }                               
        }

        context.ExecuteQuery();

I can see that the RoleDefinition is removed from the parent RoleDefinitionBindings list, but nothing happens. There is no error and the permissions on the list stays exactly as they were after the context.ExecuteQuery()

All the examples I found are showing how to remove an entire RoleAssignment, or how to delete the RoleDefinition from the site.

Answer 1

Try calling list.Update(); before context.ExecuteQuery();

Answer 2

Please check the following solution:

if (list.HasUniqueRoleAssignments)
{ 
     RoleAssignmentCollection oRoleAssignments = list.RoleAssignments;
     clientContext.Load(oRoleAssignments);
     clientContext.ExecuteQuery();

     foreach (RoleAssignment oRoleAssignment in oRoleAssignments)
     {
            clientContext.Load(oRoleAssignment, r => r.Member, r => r.RoleDefinitionBindings);
            clientContext.ExecuteQuery();
            Principal oPrincipal = oRoleAssignment.Member;
            if (oPrincipal.LoginName.Equals(userToRemove) || oPrincipal.Title.Equals(userToRemove))
            {
                  foreach (RoleDefinition rd in oRoleAssignment.RoleDefinitionBindings)
                  {
                       if (rd.RoleTypeKind == RoleType.Contributor)
                       {
                             clientContext.Load(rd); oRoleAssignment.RoleDefinitionBindings.Remove(rd);
                                    oRoleAssignment.Update();
                                    clientContext.Load(oRoleAssignment, r => r.Member, r => r.RoleDefinitionBindings);
                                    list.Update();
                                    clientContext.ExecuteQuery();
                                }
                            }
                        }
                    }
                }