如何承载本地文件，以便从C# Windows应用程序进行外部http访问

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using System.IO;

public class Startup
{
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        app.UseRouting();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapGet("/{filename}", async context =>
            {
                string filename = context.Request.RouteValues["filename"] as string;
                string filePath = Path.Combine(env.ContentRootPath, "files", filename);

                if (File.Exists(filePath))
                {
                    await context.Response.SendFileAsync(filePath);
                }
                else
                {
                    context.Response.StatusCode = 404;
                    await context.Response.WriteAsync("File not found");
                }
            });
        });
    }
}