WebRequest.GetRequestStream和LOH

我使用下面的代码将大文件上传到服务器，并注意到将FileStream复制到GetRequestStream，创建了bytes数组并保存在内存中。 这增加了大对象堆，我不想要它。 也许有人知道如何解决这个问题？

Stream formData = new FileStream(.....) HttpWebRequest request = WebRequest.Create(postUrl) as HttpWebRequest; using (Stream requestStream = request.GetRequestStream()) { Helpers.CopyStream(formData, requestStream); requestStream.Close(); } public static void CopyStream(Stream fromStream, Stream toStream) { try { int bytesRead; byte[] buffer = new byte[32768]; while (fromStream != null && (bytesRead = fromStream.Read(buffer, 0, buffer.Length)) > 0) { toStream.Write(buffer, 0, bytesRead); } } catch (IOException) { //suppress empty stream response } } 

内存分析器图。 bytes数组在GetRequestStream内部创建

Answer 1

您可以使用HttpWebRequest.AllowWriteStreamBuffering来禁用内部缓冲：

  HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.AllowWriteStreamBuffering = false; using (Stream formData = File.Open(fileName, FileMode.Open)) using (Stream requestStream = request.GetRequestStream()) { formData.CopyTo(requestStream, 32768); }