LINQ to SQL - mapping exception when using abstract base classes

Question

Problem: I would like to share code between multiple assemblies. This shared code will need to work with LINQ to SQL-mapped classes.

I\'ve encountered the same issu

Answer 1

I've had luck defining data classes in a shared assembly and consuming them in many assemblies versus mapping many assemblies' data classes to a shared contract. Using your example namespaces, put a custom DataContext and your shared data classes in TestLinq2Sql.Shared:

namespace TestLinq2Sql.Shared
{
    public class SharedContext : DataContext
    {
        public Table Users;
        public SharedContext (string connectionString) : base(connectionString) { }
    }

    [Table(Name = "Users")]
    public class User
    {
        [Column(DbType = "Int NOT NULL IDENTITY", IsPrimaryKey=true, CanBeNull = false)]
        public int Id { get; set; }

        [Column(DbType = "nvarchar(40)", CanBeNull = false)]
        public string Name { get; set; }

        [Column(DbType = "nvarchar(100)", CanBeNull = false)]
        public string Email { get; set; }
    }
}

Then consume the DataContext from any other assembly:

using (TestLinq2Sql.Shared.SharedContext shared = 
    new TestLinq2Sql.Shared.SharedContext(
        ConfigurationManager.ConnectionStrings["myConnString"].ConnectionString))
{
    var user = shared.Users.FirstOrDefault(u => u.Name == "test");
}