在到达 dotnet 核心 ASP 控制器之前拦截和读取数据

Question

我有一个标准的 asp dotnet core rest api 应用程序。 我想在数据到达控制器之前从正文中读取数据，以对该数据创建通用验证。

我接受我必须在 Startup.cs 中执行此操作，但我还没有找到我需要的类似内容。

启动程序

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

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddCors();
        services.AddControllers();
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }
        else
        {
            app.UseExceptionHandler(errorApp =>
            {
                errorApp.Run(async context =>
                {
                    context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
                    context.Response.ContentType = "text/html";
                    var ex = context.Features.Get<IExceptionHandlerFeature>();
                    if (ex != null)
                    {
                        //var err = $"<h1>Erro: {ex.Error.Message + "<br><br>" + ex.Error.InnerException + "<br><br>" + ex.Error.StackTrace}</h1>";
                        var err = $"<p>Erro: {ex.Error.Message} </p>";
                        await context.Response.WriteAsync(err, System.Text.Encoding.GetEncoding("iso-8859-1")).ConfigureAwait(false);
                        //await context.Response.WriteAsync(err).ConfigureAwait(false);
                    }
                });
            });
            app.UseHsts();
        }

        app.UseRouting();

        app.UseCors(x => x
            .AllowAnyMethod()
            .AllowAnyHeader()
            .SetIsOriginAllowed(origin => true) 
            .AllowCredentials());

        app.UseAuthorization();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });
    }
}

Answer 1

I want to read the data from the body before it arrives in the controllers to create a generic validation on that data这听起来像是您想要一个操作过滤器。 创建过滤器后，请将依赖项注入 Startup.cs 文件。

services.AddControllers(config =>
{
    config.Filters.Add<MySampleActionFilter>();
});

例如，我有一个 .net 6 api 应用程序，我创建了一个过滤器，如下所示：

using Microsoft.AspNetCore.Mvc.Filters;

namespace WebApiNet6
{
    public class MyActionFilter : IActionFilter
    {
        public void OnActionExecuting(ActionExecutingContext context)
        {
            // Do something before the action executes.
            var req = context.HttpContext.Request;
        }

        public void OnActionExecuted(ActionExecutedContext context)
        {
            // Do something after the action executes.
        }
    }
}

然后我将 Program.cs 从builder.Services.AddControllers()更改为

builder.Services.AddControllers(options =>
{
    options.Filters.Add<MyActionFilter>();
});

然后在过滤器中添加一个断点，当我调用api时，它会在进入控制器之前进入过滤器。