.Net core 3.1 简单视图返回内部服务器错误 500

Question

最近我向question 询问了有关通过网络浏览器公开控制台应用程序的问题。我收到了一个非常 helpful answer 并按照提供的 link 中的说明进行操作，但随后我似乎无法显示简单的视图，即使返回 OK 工作正常：

程序.cs

class Program
{
    static void Main(string[] args)
    {
        var host = new WebHostBuilder()
        .UseKestrel()
        .UseContentRoot(Directory.GetCurrentDirectory())
        .UseStartup<Startup>()
        .Build();

        host.Run();
    }
}

Startup.cs

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc();
    }

    public void Configure(IApplicationBuilder app)
    {
        app.UseMvc();
    }
}

Controller.cs

public class HomeController : Controller
{
    [Route("home/Index")]
    public IActionResult Index()
    {
        //return Ok("Hello from a controller");   //THIS WORKS 

        IndexModel data = new IndexModel();         //THIS RETURNS INTERNAL SERVER ERROR 500
        data.Title = "THIS";
        data.Message = "MESSAGE";
        return View(data);
    }
}

模型和索引：

public class IndexModel
{
    public string Title { get; set; }
    public string Message { get; set; }
}

@page
@model ConsoleApp1.Views.Home.IndexModel
@{
}
<div>
    <p>@Model.Title</p>
    <p>@Model.Message</p>
</div>

这是我在尝试显示视图时遇到的错误

Answer 1

请注意，您正在创建一个asp.net-core-3.1 mvc 项目。

您的项目结构应如下所示：

然后将您的Startup 更改为：

 public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllersWithViews();
     
    }

    public void Configure(IApplicationBuilder app)
    {
        app.UseRouting();

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

然后在您的project.csproj. 中将其更改为（注意它是Sdk="Microsoft.NET.Sdk.Web"）：

 <Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp3.1</TargetFramework>
    <PreserveCompilationContext />
  </PropertyGroup>

    <ItemGroup>
        <FrameworkReference Include="Microsoft.AspNetCore.App" />
    </ItemGroup>
</Project>

Answer 2

乍一看，我没有看到默认路由配置

app.UseMvc(routes =>
        {
            routes.MapRoute(
                name: "default",
                template: "{controller=Home}/{action=Index}/{id?}");
        });

我的建议是添加自定义异常中间件

app.UseMiddleware<ExceptionMiddleware>();

和自定义异常处理程序

 public class ExceptionMiddleware
{
    private readonly RequestDelegate next;

    public ExceptionMiddleware(RequestDelegate next)
    {
        this.next = next;
    }

    public async Task InvokeAsync(HttpContext httpContext)
    {
        try
        {
            await next(httpContext);
        }
        catch (Exception ex)
        {
            //inspect the exception here
        }
    }

然后在提交请求后调试并检查您收到的异常位置和类型。