/// <summary>
/// 课程类型
/// </summary>
public class CourseType : EntityBase<int>
{
public string Name { get; set; }
public string Remark { get; set; }
/// <summary>
/// 问卷
/// </summary>
public virtual Questionnaire Questionnaire { get; set; }
public virtual School School { get; set; }
public virtual IQueryable<Course> Course { get; set; }
}

public class Course : EntityBase<int>
{
[NotMapped]
public const string TableName = "Courses";
public string Name { get; set; }
public string Remark { get; set; }

/// <summary>
/// 点击量
/// </summary>
public int Count { get; set; }
/// <summary>
/// 可选人数
/// </summary>
public int AvailableCount { get; set; }
public virtual List<GradeTable> Grade { get; set; }
/// <summary>
/// 课程类型
/// </summary>
public CourseType Type { get; set; }
/// <summary>
/// 所有年级
/// </summary>
[NotMapped]
public IQueryable<GradeTable> AllGrade { get; set; }
public virtual List<Course_Period> Course_Period { get; set; }
public virtual IQueryable<Course_Extend> Course_Extend { get; set; }

}

查询代码：

A specified Include path is not valid. The EntityType 'DAL.CourseType' does not declare a navigation property with the name 'Course'.

这个问题怎么解决啊

没有园豆了，知道的帮个忙吧