C# 方法的.NET MVC接口

我需要在接口中声明方法的帮助。实施方法：

 public virtual IEnumerable<TEntity> Get(
        Expression<Func<TEntity, bool>> filter = null,
        Func<IQueryable<TEntity>, IOrderedEnumerable<TEntity>> orderBy = null,
        string includeProperties = "")
    {...
    }

---

谢谢。

以下是如何将其放入界面：

public interface IRepository
{
   IEnumerable<TEntity> Get<TEntity>(Expression<Func<TEntity, bool>> filter = null,
        Func<IQueryable<TEntity>, IOrderedEnumerable<TEntity>> orderBy = null,
        string includeProperties = "")
}

或

---

您遇到了什么错误？作为一个极其简化的经验法则，删除所有访问修饰符public、virtual等，实现将{…}替换为；。剩下的是接口方法声明…第二个非常好用。谢谢

public interface IRepository<TEntity>
{
   IEnumerable<TEntity> Get(Expression<Func<TEntity, bool>> filter = null,
        Func<IQueryable<TEntity>, IOrderedEnumerable<TEntity>> orderBy = null,
        string includeProperties = "")
}