2015-07-24-how-to-automatically-load-navigation-properties-in-entity-framework_004.cs

internal static IQueryable<TEntity> Include<TEntity>(this IQueryable<TEntity> query, DbContext context, params string[] includes) where TEntity : class
{
    // Do a safety check first
    if (includes == null)
        return query;

    List<string> includeList = new List<string>();
    if (includes.Any())
        return includes
            .Where(x => !string.IsNullOrEmpty(x) && !includeList.Contains(x))
            .Aggregate(query, (current, include) => current.Include(include));

    IEnumerable<INavigation> navigationProperties = context.Model.FindEntityType(typeof(TEntity)).GetNavigations();
    if (navigationProperties == null)
        return query;

    foreach (INavigation navigationProperty in navigationProperties)
    {
        if (includeList.Contains(navigationProperty.Name))
            continue;

        includeList.Add(navigationProperty.Name);
        query = query.Include(navigationProperty.Name);
    }

    return query;

}