在ASP.NET Web中通过中间件访问JsonOptions

public class CustomMiddleware
{
    private readonly RequestDelegate _next;
    private readonly JsonSerializerOptions _jsonOptions;

    public CustomMiddleware(RequestDelegate next)
    {
        _next = next;
        _jsonOptions = new JsonSerializerOptions();
    }

    public async Task InvokeAsync(HttpContext context)
    {
        // 尝试访问_jsonOptions，但发现它没有被正确配置
        await _next(context);
    }
}

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllers().AddJsonOptions(options =>
        {
            options.JsonSerializerOptions.IgnoreNullValues = true;
            // 其他配置...
        });
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        app.UseMiddleware<CustomMiddleware>();

        app.UseRouting();

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

public class CustomMiddleware
{
    private readonly RequestDelegate _next;
    private readonly JsonSerializerOptions _jsonOptions;

    public CustomMiddleware(RequestDelegate next, JsonSerializerOptions jsonOptions)
    {
        _next = next;
        _jsonOptions = jsonOptions;
    }

    public async Task InvokeAsync(HttpContext context)
    {
        // 现在可以正确访问_jsonOptions
        await _next(context);
    }
}