Fluent Nhibernate：映射问题

Question

我对 Fluent Nhibernate 非常陌生。我陷入了一种情况。 请查找以下详细信息。

我们的表结构就像

表学生 { Student_Id, Name}
表学校 { School_Id, 名称}
表 LinkTable { School_Id, Student_Id}

LinkTable 仅包含学生和学校的 id。 [复合键]

关系就像 1) 一名学生可以属于 0 或 1 所学校。 2) 一所学校可以容纳许多学生。

谁能告诉我如何为每个文件完成映射？

或者让 mw 知道以下映射文件中有什么问题

现在，它给我错误，在 SchoolStudent 上找不到学生属性。

  public Student()
{
    Id(x => x.Id);
    Map(x => x.Name);
    HasOne(x => x.SchoolStudent).PropertyRef(r => r.Student);
}

public School()
{
    Id(x => x.Id);
    Map(x => x.Name);
    HasMany(x => x.SchoolStudent).KeyColumn("School_Id").Inverse().Cascade.AllDeleteOrphan();
}

public SchoolStudent()
{
    CompositeId().KeyReference(x => x.School, "School_Id")
            .KeyReference(x => x.Student, "Student_Id");
}

谢谢， 马赫什

Answer 1

我会将其重写为如下内容：

Student.cs

public class Student 
{
    public virtual int Id { get; set; }
    public virtual string Name { get; set; }
    public virtual IList<School> Schools { get; set; }

    public Student() 
    {
        Schools = new List<School>();
    }
}

School.cs

public class School 
{
    public virtual int Id { get; set; }
    public virtual string Name { get; set; }
    public virtual IList<Student> Students { get; set; }

    public School() 
    {
        Students = new List<Student>();
    }
}

StudentMap.cs

public class StudentMap : ClassMap<Student>
{
    public Student()
    {
        Id(x => x.Id    , "Student_Id");
        Map(x => x.Name , "Name");

        HasManyToMany(x => x.Schools).Table("LinkTable")
                                     .ParentKeyColumn("Student_Id")
                                     .ChildKeyColumn("School_Id");
    }
}

SchoolMap.cs >

public class SchoolMap: ClassMap<School>
{
    public School()
    {
        Id(x => x.Id    , "School_Id");
        Map(x => x.Name , "Name");

        HasManyToMany(x => x.Students).Table("LinkTable")
                                      .ParentKeyColumn("School_Id")
                                      .ChildKeyColumn("Student_Id");
    }
}

Answer 2

如果一个学生只能与 0 或 1 所学校关联，那么您可以考虑删除 LinkTable 和 SchoolStudent 类，而只将 School_Id 添加到 Student 表，并在 Student 类中添加对 School 的引用。

那么你的映射就像：

public Student()
{
    Id(x => x.Id);
    Map(x => x.Name);
    References(x => x.School);
}

public School()
{
    Id(x => x.Id);
    Map(x => x.Name);
    HasMany(x => x.Student).Inverse().Cascade.AllDeleteOrphan();
}