ASP.NET Core MVC启动服务器时出现Error 404问题求助

开发兽医诊所管理系统服务器，医生可通过Web应用登录个人账户并查看排班。已编写模型、视图和控制器代码，但启动服务器时出现HTTP ERROR 404，访问/api或/doctor/login均无效。项目无默认Startup文件，系手动创建，怀疑路由或Startup配置有误。

代码片段：DoctorsController #

using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using System.Linq;
using System.Threading.Tasks;
using VetCareServ.Data;
using VetCareServ.DTO;
using VetCareServ.Models;

[Route("api/[controller]")]
[ApiController]
public class DoctorsController : ControllerBase
{
    private readonly VetCareServDbContext _context;

    public DoctorsController(VetCareServDbContext context)
    {
        _context = context;
    }

    [HttpPost("login")]
    public async Task<IActionResult> Login([FromBody] DoctorLoginModel doctorLogin)
    {
        if (ModelState.IsValid)
        {
            var authenticatedDoctor = await _context.DoctorLoginModel
                .FirstOrDefaultAsync(d => d.DoctorEmail == doctorLogin.DoctorEmail && d.DoctorPassHash == doctorLogin.DoctorPassHash);

            if (authenticatedDoctor != null)
            {
                var doctorInfo = await _context.Doctors
                    .FirstOrDefaultAsync(d => d.DoctorEmail == doctorLogin.DoctorEmail);

                return RedirectToAction("Account", new { id = doctorInfo.DoctorId });
            }
            else
            {
                ModelState.AddModelError(string.Empty, "Неверные учетные данные");
                return BadRequest(ModelState);
            }
        }

        return BadRequest(ModelState);
    }

    [HttpGet("account/{id}")]
    public async Task<IActionResult> Account(int id)
    {
        var doctor = await _context.Doctors.FindAsync(id);

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

        return Ok(doctor);
    }
}

代码片段：Startup.cs #

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using VetCareServ.Data;

namespace VetCareServ
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<VetCareServDbContext>(options =>
                options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

            services.AddControllersWithViews();
            services.AddSession();
        }

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
                app.UseHsts();
            }

            app.UseSession();
       
            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Doctor}/{action=Login}/{id?}");//it seems to be right!
            });

            app.UseHttpsRedirection();
            app.UseStaticFiles();
            
            app.UseRouting();

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Home}/{action=Index}/{id?}");
            });
        }
    }
}

一、修复Startup配置中的核心问题 #

1. 修正中间件顺序：ASP.NET Core中间件必须按固定顺序执行，当前UseEndpoints调用在UseRouting、UseHttpsRedirection之前，会导致路由逻辑失效。正确顺序为：异常处理 → HSTS → HTTPS重定向 → 静态文件 → Session → 路由 → 授权 → 端点映射。
2. 合并并修正路由配置：代码中重复配置同名默认路由，且未单独映射API控制器。修改后的Configure方法如下：

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    if (env.IsDevelopment())
    {
        app.UseDeveloperExceptionPage();
    }
    else
    {
        app.UseExceptionHandler("/Home/Error");
        app.UseHsts();
    }

    app.UseHttpsRedirection();
    app.UseStaticFiles();
    
    app.UseSession();
    app.UseRouting();

    app.UseAuthorization();

    app.UseEndpoints(endpoints =>
    {
        // 优先映射API控制器（支持属性路由）
        endpoints.MapControllers();
        // 配置MVC页面默认路由
        endpoints.MapControllerRoute(
            name: "default",
            pattern: "{controller=Home}/{action=Index}/{id?}");
    });
}

二、修正API访问路径 #

你的DoctorsController使用属性路由[Route("api/[controller]")]，正确的访问路径应为：

• 登录接口：POST /api/Doctors/login（控制器名称为复数Doctors，而非doctor）
• 账户信息接口：GET /api/Doctors/account/{id}

三、API逻辑优化 #

1. 移除API中的重定向逻辑：REST API应返回JSON数据而非页面重定向，前端收到成功响应后自行处理跳转逻辑。修改Login方法：

[HttpPost("login")]
public async Task<IActionResult> Login([FromBody] DoctorLoginModel doctorLogin)
{
    if (!ModelState.IsValid)
    {
        return BadRequest(ModelState);
    }

    var authenticatedDoctor = await _context.DoctorLoginModel
        .FirstOrDefaultAsync(d => d.DoctorEmail == doctorLogin.DoctorEmail && d.DoctorPassHash == doctorLogin.DoctorPassHash);

    if (authenticatedDoctor == null)
    {
        ModelState.AddModelError(string.Empty, "Неверные учетные данные");
        return Unauthorized(ModelState); // 使用401状态码更符合REST规范
    }

    var doctorInfo = await _context.Doctors
        .FirstOrDefaultAsync(d => d.DoctorEmail == doctorLogin.DoctorEmail);

    if (doctorInfo == null)
    {
        return NotFound("医生信息不存在");
    }

    return Ok(new { DoctorId = doctorInfo.DoctorId, DoctorInfo = doctorInfo });
}

2. 密码安全优化：建议使用ASP.NET Core内置的PasswordHasher<T>进行密码哈希与验证，避免直接比较哈希值的安全风险。

四、其他排查要点 #

• 确认VetCareServDbContext中的DoctorLoginModel和Doctors集合已正确映射到数据库表。
• 开发环境下保留UseDeveloperExceptionPage，可查看详细错误堆栈信息，快速定位问题。

内容的提问来源于stack exchange，提问作者Daniel