C# MemoryStream、StreamWriter

        public async Task ExecuteAsync(HttpContext context)
        {
            Context = context;
            Request = Context.Request;
            Response = Context.Response;
            var buffer = new MemoryStream();
            Output = new StreamWriter(buffer, UTF8NoBOM, 4096, leaveOpen: true);
            await ExecuteAsync();
            await Output.FlushAsync();
            await Output.DisposeAsync();
            buffer.Seek(0, SeekOrigin.Begin);
            await buffer.CopyToAsync(Response.Body);
        }

因为 MemoryStream 是内存流，因此不需要 Dispose，GC 回收的时候会自动释放。