如何在Asp.Net中间件中抛出错误

public class MyCustomException : Exception
{
    public MyCustomException(string message) : base(message)
    {
    }
}

app.UseExceptionHandler(errorApp =>
{
    errorApp.Run(async context =>
    {
        context.Response.StatusCode = (int)HttpStatusCode.InternalServerError;
        context.Response.ContentType = "text/plain";

        var exceptionHandlerFeature = context.Features.Get<IExceptionHandlerFeature>();
        if (exceptionHandlerFeature != null)
        {
            var errorMessage = exceptionHandlerFeature.Error.Message;

            // 在这里记录日志或其他操作

            await context.Response.WriteAsync(errorMessage);
        }
    });
});

app.UseMiddleware<ErrorHandlingMiddleware>();
// 添加其他中间件