c# - 升级到 .net core 3.0 后报错“找不到网页地址为 : https://localhost:44374/"的网页

Question

我将具有 2 个类库和一个 Mvc 项目的项目从 2.2 升级到 MVC Core 3.0
这个页面
enter link description here

更改.net <TargetFramework>netcoreapp3.0</TargetFramework>
2.改成这样
<ItemGroup>
<!--<PackageReference Include="Microsoft.AspNetCore.App" />-->
<!--<PackageReference Include="Microsoft.AspNetCore.Identity" Version="2.2.0" />-->
<PackageReference Include="Microsoft.AspNetCore.Identity.UI" Version="3.0.0" />
<!--<PackageReference Include="Microsoft.AspNetCore.Razor.Design" Version="2.2.0" PrivateAssets="All" />-->
<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="3.0.0" />
</ItemGroup>
3.my sattup.cs

`
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseDefaultFiles();
app.UseCookiePolicy();

    app.UseRouting();

    app.UseAuthorization();

    app.UseEndpoints(endpoints =>
    {
        endpoints.MapRazorPages();
    });`

我的程序.cs

public static void Main(string[] args)
{
CreateHostBuilder(args).Build().Run();
}
公共(public)静态 IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
.ConfigureWebHostDefaults(webBuilder =>
{
webBuilder.UseStartup();
});

但是当我运行我的项目时出现这个错误

This localhost page can’t be foundNo webpage was found for the web address: https://localhost:44374/ HTTP ERROR 404

Answer 1

在 Startup.cs尝试这个

public void ConfigureServices(IServiceCollection services) 
{
           //Code above . . .

            services.AddMvc( options =>
            {
                options.EnableEndpointRouting = false;
            });

            //Code below. . .
}

然后在

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            //Code above . . .

            app.UseMvcWithDefaultRoute();

            //Code below. . .
        }

并删除

    app.UseEndpoints(endpoints =>
    {
        endpoints.MapRazorPages();
    });`