C# 如何创建API端点以获取包括学生在内的部门？_C#_Entity Framework_Linq_Asp.net Core Webapi_Endpoint

C# 如何创建API端点以获取包括学生在内的部门？

c# entity-framework linq

C# 如何创建API端点以获取包括学生在内的部门？,c#,entity-framework,linq,asp.net-core-webapi,endpoint,C#,Entity Framework,Linq,Asp.net Core Webapi,Endpoint,我已经用学生和系实体实现了一个.net核心web api。这些实体之间实现了一对一的关系，其中departmentid是学生表的foreignkey。如何在DepartmentController中实现api端点以获取包含学生的所有部门 DepartmentController.cs using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Micr

我已经用学生和系实体实现了一个.net核心web api。这些实体之间实现了一对一的关系，其中departmentid是学生表的foreignkey。如何在DepartmentController中实现api端点以获取包含学生的所有部门

DepartmentController.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Students.Models;

namespace Students.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class DepartmentController : ControllerBase
    {
        private readonly StudentContext _context;

        public DepartmentController(StudentContext context)
        {
            _context = context;
        }

        // GET: api/Department
        [HttpGet]
        public async Task<ActionResult<IEnumerable<Department>>> GetDepartments()
        {
            return await _context.Departments.ToListAsync();
        }

        // GET: api/Department/5
        [HttpGet("{id}")]
        public async Task<ActionResult<Department>> GetDepartment(int id)
        {
            var department = await _context.Departments.FindAsync(id);

            if (department == null)
            {
                return NotFound();
            }

            return department;
        }

        // PUT: api/Department/5
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPut("{id}")]
        public async Task<IActionResult> PutDepartment(int id, Department department)
        {
            if (id != department.Id)
            {
                return BadRequest();
            }

            _context.Entry(department).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!DepartmentExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return Ok();
        }

        // POST: api/Department
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPost]
        public async Task<ActionResult<Department>> PostDepartment(Department department)
        {
            _context.Departments.Add(department);
            await _context.SaveChangesAsync();

            return CreatedAtAction("GetDepartment", new { id = department.Id }, department);
        }

        // DELETE: api/Department/5
        [HttpDelete("{id}")]
        public async Task<ActionResult<Department>> DeleteDepartment(int id)
        {
            var department = await _context.Departments.FindAsync(id);
            if (department == null)
            {
                return NotFound();
            }

            _context.Departments.Remove(department);
            await _context.SaveChangesAsync();

            return department;
        }

        private bool DepartmentExists(int id)
        {
            return _context.Departments.Any(e => e.Id == id);
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;

namespace Students.Models
{
    public class Department
    {
        [Key]
        public int Id { get; set; }
        [Required]
        [Column(TypeName = "varchar(20)")]
        public string Dep { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;

namespace Students.Models
{
    public class Student
    {
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int SId { get; set; }
        [Required]
        [Column(TypeName ="varchar(50)")]
        public string Name { get; set; }
        public int DepartmentId { get; set; }
        public Department Department { get; set; }
    }
}

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;

namespace Students.Models
{
    public class StudentContext:DbContext
    {
        public StudentContext(DbContextOptions<StudentContext> options) : base(options)
        {

        }
        public DbSet<Student> Students { get; set; }
        public DbSet<Department> Departments { get; set; }
    }
}

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Students.Models;

namespace Students.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class StudentsController : ControllerBase
    {
        private readonly StudentContext _context;

        public StudentsController(StudentContext context)
        {
            _context = context;
        }

        // GET: api/Students
        [HttpGet]
        public async Task<ActionResult<IEnumerable<Student>>> GetStudents()
        {
            return await _context.Students.Include(d => d.Department).ToListAsync();
        }

        // GET: api/Students/5
        [HttpGet("{id}")]
        public async Task<ActionResult<Student>> GetStudent(int id)
        {
            var student = await _context.Students.Include(d => d.Department).FirstOrDefaultAsync(i => i.SId == id);

            if (student == null)
            {
                return NotFound();
            }

            return student;
        }

        // PUT: api/Students/5
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPut("{id}")]
        public async Task<IActionResult> PutStudent(int id, Student student)
        {
            if (id != student.SId)
            {
                return BadRequest();
            }
            _context.Departments.Update(student.Department);
            await _context.SaveChangesAsync();
            _context.Entry(student).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!StudentExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return Ok();
        }

        // POST: api/Students
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPost]
        public async Task<ActionResult<Student>> PostStudent(List<Student> student)
        {
            try
            {
                for (var i = 0; i < student.ToArray().Length; i++)
                {
                    _context.Students.Add(student[i]);
                }
                _context.SaveChanges();
                return CreatedAtAction("GetStudents", student);
            }
            catch
            {
                return BadRequest();
            }

            /*_context.Students.Add(student);
            await _context.SaveChangesAsync();

            return CreatedAtAction("GetStudent", new { id = student.SId }, student);*/
        }


        /*[HttpPost]
        [Route("StudentList")]
        public async Task<ActionResult<Student>> PostStudentList([FromBody] List<Student> student)
        {
            try
            {
                for (var i = 0; i < student.ToArray().Length; i++)
                {
                    _context.Students.Add(student[i]);
                }
                _context.SaveChanges();
                return CreatedAtAction("GetStudents", student);
            }
            catch
            {
                return BadRequest();
            }
        }*/

        // DELETE: api/Students/5
        [HttpDelete("{id}")]
        public async Task<ActionResult<Student>> DeleteStudent(int id)
        {
            var student = await _context.Students.FindAsync(id);
            if (student == null)
            {
                return NotFound();
            }

            _context.Students.Remove(student);
            await _context.SaveChangesAsync();

            return student;
        }

        private bool StudentExists(int id)
        {
            return _context.Students.Any(e => e.SId == id);
        }
    }
}

Student.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Students.Models;

namespace Students.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class DepartmentController : ControllerBase
    {
        private readonly StudentContext _context;

        public DepartmentController(StudentContext context)
        {
            _context = context;
        }

        // GET: api/Department
        [HttpGet]
        public async Task<ActionResult<IEnumerable<Department>>> GetDepartments()
        {
            return await _context.Departments.ToListAsync();
        }

        // GET: api/Department/5
        [HttpGet("{id}")]
        public async Task<ActionResult<Department>> GetDepartment(int id)
        {
            var department = await _context.Departments.FindAsync(id);

            if (department == null)
            {
                return NotFound();
            }

            return department;
        }

        // PUT: api/Department/5
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPut("{id}")]
        public async Task<IActionResult> PutDepartment(int id, Department department)
        {
            if (id != department.Id)
            {
                return BadRequest();
            }

            _context.Entry(department).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!DepartmentExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return Ok();
        }

        // POST: api/Department
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPost]
        public async Task<ActionResult<Department>> PostDepartment(Department department)
        {
            _context.Departments.Add(department);
            await _context.SaveChangesAsync();

            return CreatedAtAction("GetDepartment", new { id = department.Id }, department);
        }

        // DELETE: api/Department/5
        [HttpDelete("{id}")]
        public async Task<ActionResult<Department>> DeleteDepartment(int id)
        {
            var department = await _context.Departments.FindAsync(id);
            if (department == null)
            {
                return NotFound();
            }

            _context.Departments.Remove(department);
            await _context.SaveChangesAsync();

            return department;
        }

        private bool DepartmentExists(int id)
        {
            return _context.Departments.Any(e => e.Id == id);
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;

namespace Students.Models
{
    public class Department
    {
        [Key]
        public int Id { get; set; }
        [Required]
        [Column(TypeName = "varchar(20)")]
        public string Dep { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;

namespace Students.Models
{
    public class Student
    {
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int SId { get; set; }
        [Required]
        [Column(TypeName ="varchar(50)")]
        public string Name { get; set; }
        public int DepartmentId { get; set; }
        public Department Department { get; set; }
    }
}

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;

namespace Students.Models
{
    public class StudentContext:DbContext
    {
        public StudentContext(DbContextOptions<StudentContext> options) : base(options)
        {

        }
        public DbSet<Student> Students { get; set; }
        public DbSet<Department> Departments { get; set; }
    }
}

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Students.Models;

namespace Students.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class StudentsController : ControllerBase
    {
        private readonly StudentContext _context;

        public StudentsController(StudentContext context)
        {
            _context = context;
        }

        // GET: api/Students
        [HttpGet]
        public async Task<ActionResult<IEnumerable<Student>>> GetStudents()
        {
            return await _context.Students.Include(d => d.Department).ToListAsync();
        }

        // GET: api/Students/5
        [HttpGet("{id}")]
        public async Task<ActionResult<Student>> GetStudent(int id)
        {
            var student = await _context.Students.Include(d => d.Department).FirstOrDefaultAsync(i => i.SId == id);

            if (student == null)
            {
                return NotFound();
            }

            return student;
        }

        // PUT: api/Students/5
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPut("{id}")]
        public async Task<IActionResult> PutStudent(int id, Student student)
        {
            if (id != student.SId)
            {
                return BadRequest();
            }
            _context.Departments.Update(student.Department);
            await _context.SaveChangesAsync();
            _context.Entry(student).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!StudentExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return Ok();
        }

        // POST: api/Students
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPost]
        public async Task<ActionResult<Student>> PostStudent(List<Student> student)
        {
            try
            {
                for (var i = 0; i < student.ToArray().Length; i++)
                {
                    _context.Students.Add(student[i]);
                }
                _context.SaveChanges();
                return CreatedAtAction("GetStudents", student);
            }
            catch
            {
                return BadRequest();
            }

            /*_context.Students.Add(student);
            await _context.SaveChangesAsync();

            return CreatedAtAction("GetStudent", new { id = student.SId }, student);*/
        }


        /*[HttpPost]
        [Route("StudentList")]
        public async Task<ActionResult<Student>> PostStudentList([FromBody] List<Student> student)
        {
            try
            {
                for (var i = 0; i < student.ToArray().Length; i++)
                {
                    _context.Students.Add(student[i]);
                }
                _context.SaveChanges();
                return CreatedAtAction("GetStudents", student);
            }
            catch
            {
                return BadRequest();
            }
        }*/

        // DELETE: api/Students/5
        [HttpDelete("{id}")]
        public async Task<ActionResult<Student>> DeleteStudent(int id)
        {
            var student = await _context.Students.FindAsync(id);
            if (student == null)
            {
                return NotFound();
            }

            _context.Students.Remove(student);
            await _context.SaveChangesAsync();

            return student;
        }

        private bool StudentExists(int id)
        {
            return _context.Students.Any(e => e.SId == id);
        }
    }
}

StudentContext.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Students.Models;

namespace Students.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class DepartmentController : ControllerBase
    {
        private readonly StudentContext _context;

        public DepartmentController(StudentContext context)
        {
            _context = context;
        }

        // GET: api/Department
        [HttpGet]
        public async Task<ActionResult<IEnumerable<Department>>> GetDepartments()
        {
            return await _context.Departments.ToListAsync();
        }

        // GET: api/Department/5
        [HttpGet("{id}")]
        public async Task<ActionResult<Department>> GetDepartment(int id)
        {
            var department = await _context.Departments.FindAsync(id);

            if (department == null)
            {
                return NotFound();
            }

            return department;
        }

        // PUT: api/Department/5
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPut("{id}")]
        public async Task<IActionResult> PutDepartment(int id, Department department)
        {
            if (id != department.Id)
            {
                return BadRequest();
            }

            _context.Entry(department).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!DepartmentExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return Ok();
        }

        // POST: api/Department
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPost]
        public async Task<ActionResult<Department>> PostDepartment(Department department)
        {
            _context.Departments.Add(department);
            await _context.SaveChangesAsync();

            return CreatedAtAction("GetDepartment", new { id = department.Id }, department);
        }

        // DELETE: api/Department/5
        [HttpDelete("{id}")]
        public async Task<ActionResult<Department>> DeleteDepartment(int id)
        {
            var department = await _context.Departments.FindAsync(id);
            if (department == null)
            {
                return NotFound();
            }

            _context.Departments.Remove(department);
            await _context.SaveChangesAsync();

            return department;
        }

        private bool DepartmentExists(int id)
        {
            return _context.Departments.Any(e => e.Id == id);
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;

namespace Students.Models
{
    public class Department
    {
        [Key]
        public int Id { get; set; }
        [Required]
        [Column(TypeName = "varchar(20)")]
        public string Dep { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;

namespace Students.Models
{
    public class Student
    {
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int SId { get; set; }
        [Required]
        [Column(TypeName ="varchar(50)")]
        public string Name { get; set; }
        public int DepartmentId { get; set; }
        public Department Department { get; set; }
    }
}

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;

namespace Students.Models
{
    public class StudentContext:DbContext
    {
        public StudentContext(DbContextOptions<StudentContext> options) : base(options)
        {

        }
        public DbSet<Student> Students { get; set; }
        public DbSet<Department> Departments { get; set; }
    }
}

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Students.Models;

namespace Students.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class StudentsController : ControllerBase
    {
        private readonly StudentContext _context;

        public StudentsController(StudentContext context)
        {
            _context = context;
        }

        // GET: api/Students
        [HttpGet]
        public async Task<ActionResult<IEnumerable<Student>>> GetStudents()
        {
            return await _context.Students.Include(d => d.Department).ToListAsync();
        }

        // GET: api/Students/5
        [HttpGet("{id}")]
        public async Task<ActionResult<Student>> GetStudent(int id)
        {
            var student = await _context.Students.Include(d => d.Department).FirstOrDefaultAsync(i => i.SId == id);

            if (student == null)
            {
                return NotFound();
            }

            return student;
        }

        // PUT: api/Students/5
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPut("{id}")]
        public async Task<IActionResult> PutStudent(int id, Student student)
        {
            if (id != student.SId)
            {
                return BadRequest();
            }
            _context.Departments.Update(student.Department);
            await _context.SaveChangesAsync();
            _context.Entry(student).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!StudentExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return Ok();
        }

        // POST: api/Students
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see https://aka.ms/RazorPagesCRUD.
        [HttpPost]
        public async Task<ActionResult<Student>> PostStudent(List<Student> student)
        {
            try
            {
                for (var i = 0; i < student.ToArray().Length; i++)
                {
                    _context.Students.Add(student[i]);
                }
                _context.SaveChanges();
                return CreatedAtAction("GetStudents", student);
            }
            catch
            {
                return BadRequest();
            }

            /*_context.Students.Add(student);
            await _context.SaveChangesAsync();

            return CreatedAtAction("GetStudent", new { id = student.SId }, student);*/
        }


        /*[HttpPost]
        [Route("StudentList")]
        public async Task<ActionResult<Student>> PostStudentList([FromBody] List<Student> student)
        {
            try
            {
                for (var i = 0; i < student.ToArray().Length; i++)
                {
                    _context.Students.Add(student[i]);
                }
                _context.SaveChanges();
                return CreatedAtAction("GetStudents", student);
            }
            catch
            {
                return BadRequest();
            }
        }*/

        // DELETE: api/Students/5
        [HttpDelete("{id}")]
        public async Task<ActionResult<Student>> DeleteStudent(int id)
        {
            var student = await _context.Students.FindAsync(id);
            if (student == null)
            {
                return NotFound();
            }

            _context.Students.Remove(student);
            await _context.SaveChangesAsync();

            return student;
        }

        private bool StudentExists(int id)
        {
            return _context.Students.Any(e => e.SId == id);
        }
    }
}

使用System.Collections.Generic；
使用System.Linq；
使用System.Threading.Tasks；
使用Microsoft.EntityFrameworkCore；
名称空间学生。模型
{
公共类StudentContext:DbContext
{
public StudentContext（DbContextOptions）：基本（选项）
{
}
公共数据库集学生{get；set；}
公共数据库集部门{get；set；}
}
}

StudentController.cs 请参考GetStudents（）

使用System.Collections.Generic；
使用System.Linq；
使用System.Threading.Tasks；
使用Microsoft.AspNetCore.Http；
使用Microsoft.AspNetCore.Mvc；
使用Microsoft.EntityFrameworkCore；
使用学生模型；
名称空间学生。控制器
{
[路由（“api/[控制器]”）]
[ApiController]
公共班级学生控制员：控制员数据库
{
私有只读StudentContext\u context；
公共学生控制器（学生上下文）
{
_上下文=上下文；
}
//获取：api/学生
[HttpGet]
公共异步任务GetStudents（）
{
return wait_context.Students.Include（d=>d.Department.toListSync（）；
}
//获取：api/Students/5
[HttpGet（“{id}”）]
公共异步任务GetStudent（int id）
{
var student=wait _context.Students.Include（d=>d.Department）.FirstOrDefaultAsync（i=>i.SId==id）；
如果（学生==null）
{
返回NotFound（）；
}
留学生；
}
//PUT:api/Students/5
//若要防止套印攻击，请启用要绑定到的特定属性，例如
//更多详细信息请参见https://aka.ms/RazorPagesCRUD.
[HttpPut（“{id}”）]
公共异步任务PutStudent（int-id，Student-Student）
{
if（id！=student.SId）
{
返回请求（）；
}
_上下文。系。更新（学生。系）；
wait_context.SaveChangesAsync（）；
_context.Entry（student.State=EntityState.Modified；
尝试
{
wait_context.SaveChangesAsync（）；
}
catch（DbUpdateConcurrencyException）
{
如果（！StudentExists（id））
{
返回NotFound（）；
}
其他的
{
投掷；
}
}
返回Ok（）；
}
//职位：api/学生
//若要防止套印攻击，请启用要绑定到的特定属性，例如
//更多详细信息请参见https://aka.ms/RazorPagesCRUD.
[HttpPost]
公共异步任务PostStudent（学生列表）
{
尝试
{
for（var i=0；ie.SId==id）；
}
}
}

您要查找的可能是：在学生上下文中使用include方法包括该系，如下所示：

context.Students.Include(student => student.Department);

可能是您必须更新映射，以便EF能够理解它。在这种情况下，如果需要，在映射中需要包含一个HasOne（student=>student.Department）。或者在部门映射中，使用HasMany（Department=>Department.Students）（但您的部门没有学生集合，因此除非您更改模型，否则后者将不是选项）

修改

部门

类以包含

学生

导航属性

public virtual Student Student { get; set; }

然后在

GetDepartments（）

方法中，包含Student属性

var query = _context.Departments.Include(d => d.Student);

它返回一个IQueryable，因此您可以添加另一个筛选

var filteredQuery = query.Where(d => d.Student.Name.Contains("jane"));

在你还它之前

return query.ToList();

或

我试过这个。但它在学生和系之间造成了循环依赖

如上所述，您可以在

D中添加Student
导航属性