how to create a generic T object dynamically

[m.scofield]

  public T GetReposit<T>() where T : class        {
            var result = default(T);
            if (typeof(T) == typeof(UserRepository))
            {
                result = new UserRepository(Context) as T;
            }
            if (typeof(T) == typeof(ProductRepository))
            {
                result = (T)(object)new ProductRepository(Context);
            }
            if (typeof(T) == typeof(CustomerRepository))
            {
                result = (T)(object)new CustomerRepository(Context);
            }
            // etc....
           
            return result;
        }
// when i have BaseListPage
public class BaseListPage<TEntity, TRepository> : BasePage
					where TEntity : Tentity
					where TRepository : BaseRepository<TEntity> {
		protected TRepository _repository;


		public BaseListPage() {
			UnitOfWork unit = UnitOfWork.Instance;
			_repository = unit.GetRepository<TRepository>();
		}
//it actually works but i want to optimize this code