上传文件,之前使用WebClient的上传方法,UploadFile方法容易造成内存溢出,UploadData方法又一直没搞定,所以借鉴下网友的方法
文章主要内容源自(http://blogs.msdn.com/b/johan/archive/2006/11/15/are-you-getting-outofmemoryexceptions-when-uploading-large-files.aspx),本文做些修改,使其可直接使用:
原文链接:https://blog.csdn.net/u012790747/java/article/details/46052519
public static string MyUploader(string strFileToUpload, string strUrl,Action<double,double> uploading) { string strFileFormName = "file"; Uri oUri = new Uri(strUrl); string strBoundary = "----------" + DateTime.Now.Ticks.ToString("x"); // The trailing boundary string byte[] boundaryBytes = Encoding.ASCII.GetBytes(" --" + strBoundary + "-- "); //**注意此处的 strBoundary后的换行前加上--,不然会异常** // The post message header StringBuilder sb = new StringBuilder(); sb.Append("--"); sb.Append(strBoundary); sb.Append(" "); sb.Append("Content-Disposition: form-data; name=""); sb.Append(strFileFormName); sb.Append(""; filename=""); sb.Append(Path.GetFileName(strFileToUpload)); sb.Append("""); sb.Append(" "); sb.Append("Content-Type: "); sb.Append("application/octet-stream"); sb.Append(" "); sb.Append(" "); string strPostHeader = sb.ToString(); byte[] postHeaderBytes = Encoding.UTF8.GetBytes(strPostHeader); // The WebRequest HttpWebRequest oWebrequest = (HttpWebRequest)WebRequest.Create(oUri); oWebrequest.ContentType = "multipart/form-data; boundary=" + strBoundary; oWebrequest.Method = "POST"; // This is important, otherwise the whole file will be read to memory anyway... oWebrequest.AllowWriteStreamBuffering = false; // Get a FileStream and set the final properties of the WebRequest FileStream oFileStream = new FileStream(strFileToUpload, FileMode.Open, FileAccess.Read); long length = postHeaderBytes.Length + oFileStream.Length + boundaryBytes.Length; oWebrequest.ContentLength = length; Stream oRequestStream = oWebrequest.GetRequestStream(); // Write the post header oRequestStream.Write(postHeaderBytes, 0, postHeaderBytes.Length); // Stream the file contents in small pieces (4096 bytes, max). byte[] buffer = new Byte[checked((uint)Math.Min(4096, (int)oFileStream.Length))]; int bytesRead = 0; double size=0; while ((bytesRead = oFileStream.Read(buffer, 0, buffer.Length)) != 0) { oRequestStream.Write(buffer, 0, bytesRead); size+=bytesRead; if(uploading!=null)uploading(length ,size); } oFileStream.Close(); // Add the trailing boundary oRequestStream.Write(boundaryBytes, 0, boundaryBytes.Length); WebResponse oWResponse = oWebrequest.GetResponse(); Stream s = oWResponse.GetResponseStream(); StreamReader sr = new StreamReader(s); String sReturnString = sr.ReadToEnd(); // Clean up oFileStream.Close(); oRequestStream.Close(); s.Close(); sr.Close(); return sReturnString; } ———————————————— 版权声明:本文为CSDN博主「小学徒再来」的原创文章,遵循CC 4.0 BY-SA版权协议,转载请附上原文出处链接及本声明。 原文链接:https://blog.csdn.net/u012790747/java/article/details/46052519
如果有增加取消功能,可以调用oWebrequest的Abort方法取消上传请求。