.Net core web api - 如何在控制器中实现 PUT、POST 和 DELETE 方法？

Question

在此，我已经实现（出于实践目的）两个实体 Student 和 Department 之间的一对一关系，其中每个部门可以有一个学生。学生表具有 DepartmentId 作为外键。 [HttpGet] 和 [HttpGet({"id"})] 方法通过使用 Include() 将部门实体包含在学生中相应地实现。如何在 StudentController.cs 文件中实现 PUT、POST 和 DELETE 方法，以便与 GET 请求类似，包含部门实体。

Student.cs

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; }
    }
}

Department.cs

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; }
    }
}

StudentContext.cs

using System;
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; }
    }
}

StudentController.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 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.Entry(student).State = EntityState.Modified;

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

            return NoContent();
        }

        // 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(Student student)
        {
            _context.Students.Add(student);
            await _context.SaveChangesAsync();

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

        // 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);
        }
    }
}

Answer 1

这是一个简单的演示，如下所示：

1.POST（确保不需要传递任何id）：

[HttpPost]
public async Task<ActionResult<Student>> PostStudent(Student student)
{
    _context.Departments.Add(student.Department);
    await _context.SaveChangesAsync();

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

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

邮递员：

2.PUT：

[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 NoContent();
}

邮递员： 3.删除：

和你一样。

[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;
}