如何在启动 class 时传递一些属性并在控制器上初始化它

Question

我有一个 .net core 3.1 后台应用程序，我在其中根据实现跨越 kestrel 服务器。我需要的是在启动时配置一些属性（比方说int channel id）

启动

internal class Startup
{
    internal static IHostBuilder CreateHostBuilder(MyConfigurations _objSettings)
    {
    
        //_objSettings.channelId need to be assigned to CallBackController channelID
        return Host
            .CreateDefaultBuilder()
            .ConfigureWebHostDefaults(webBuilder => 
                webBuilder.UseUrls(_objSettings.CallbackLocalListener)
            )
            .UseStartup<Startup>());
    }

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllers(options => options.RespectBrowserAcceptHeader = true);
        services.Configure<ForwardedHeadersOptions>(options =>
        {
            options.ForwardedHeaders = ForwardedHeaders.XForwardedFor | ForwardedHeaders.XForwardedProto;
        });
    }

    public void Configure(IApplicationBuilder app)
    {
        app.UseHttpsRedirection();
        app.UseRouting();
        app.UseForwardedHeaders();
        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllerRoute("default", "{controller=Home}/{action=Index}/{id?}");
        });
    }
}

控制器

[Produces("application/json")]
public class CallBackController : ControllerBase
{          
    int channelId = 0;//this need to be initializes 

    public IActionResult Receive()
    {
        IActionResult result = null;
       
        return result;
    }
}

我需要这个，因为 class 多个实例将在其他端口上启动 kestrel 实例，监听不同的流量。在收到请求时，我需要那个频道 ID 来初始化一些东西

Answer 1

创建一个类型来存储所需的选项

public class ChannelOptions {
    public int ChannelId { get; set; }
}

并在 Startup 中使用 convivence 成员进行配置

internal static IHostBuilder CreateHostBuilder(MyConfigurations _objSettings) {        
    return Host
        .CreateDefaultBuilder()
        .ConfigureServices(services => 
            services.AddSingleton(
                new ChannelOptions {
                    ChannelId = _objSettings.channelID
                }
            )
        )
        .ConfigureWebHostDefaults(webBuilder => 
            webBuilder.UseUrls(_objSettings.CallbackLocalListener)
        )
        .UseStartup<Startup>());
}

最后，将选项作为依赖显式注入控制器

[Produces("application/json")]
public class CallBackController : ControllerBase {

    private readonly int channelId = 0;

    public CallBackController(ChannelOptions options) {
        channelId = options?.ChannelId ?? 0;
    }

    public IActionResult Receive() {
        IActionResult result = null;
       
        return result;
    }
    
    //...
}

如何在启动 class 时传递一些属性并在控制器上初始化它

How to pass some property on startup class and initialize it on controller

c#

kestrel-http-server

asp.net-core-3.1

如何在启动 class 时传递一些 属性 并在控制器上初始化它

How to pass some property on startup class and initialize it on controller

c#

kestrel-http-server

asp.net-core-3.1

如何在启动 class 时传递一些属性并在控制器上初始化它