如何使用HttpWebRequest模拟浏览器文件上传
伙计们，首先感谢您的贡献，我在这里找到了很好的回复。 然而，我遇到了一个我无法弄清楚的问题，如果有人可以提供任何帮助，我将不胜感激。
我正在用C＃开发这个应用程序，可以将图像从计算机上传到用户的photoblog。 为此，我是用于主要用PHP编写的photoblogs的pixig pixelpost平台。
我在这里和其他网页上搜索过，但那里提供的例子对我没用。 以下是我在我的示例中使用的内容:( 使用HTTPWebrequest上传文件（multipart / form-data） ）和（ http://bytes.com/topic/c-sharp/answers/268661-how-upload-file-via- c-code ）一旦准备就绪，我将在互联网上免费提供，也可以创建一个Windows移动版本，因为我是pixpost的粉丝。
这是我用过的代码：
string formUrl = "http://localhost/pixelpost/admin/index.php?x=login"; string formParams = string.Format("user={0}&password={1}", "user-String", "password-String"); string cookieHeader; HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(formUrl); req.ContentType = "application/x-www-form-urlencoded"; req.Method = "POST"; req.AllowAutoRedirect = false; byte[] bytes = Encoding.ASCII.GetBytes(formParams); req.ContentLength = bytes.Length; using (Stream os = req.GetRequestStream()) { os.Write(bytes, 0, bytes.Length); } HttpWebResponse resp = (HttpWebResponse)req.GetResponse(); cookieHeader = resp.Headers["Set-Cookie"]; string pageSource; using (StreamReader sr = new StreamReader(resp.GetResponseStream())) { pageSource = sr.ReadToEnd(); Console.WriteLine(); } string getUrl = "http://localhost/pixelpost/admin/index.php"; HttpWebRequest getRequest = (HttpWebRequest)HttpWebRequest.Create(getUrl); getRequest.Headers.Add("Cookie", cookieHeader); HttpWebResponse getResponse = (HttpWebResponse)getRequest.GetResponse(); using (StreamReader sr = new StreamReader(getResponse.GetResponseStream())) { pageSource = sr.ReadToEnd(); } // end first part: login to admin panel long length = 0; string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x"); HttpWebRequest httpWebRequest2 = (HttpWebRequest)WebRequest.Create("http://localhost/pixelpost/admin/index.php?x=save"); httpWebRequest2.ContentType = "multipart/form-data; boundary=" + boundary; httpWebRequest2.Method = "POST"; httpWebRequest2.AllowAutoRedirect = false; httpWebRequest2.KeepAlive = false; httpWebRequest2.Credentials = System.Net.CredentialCache.DefaultCredentials; httpWebRequest2.Headers.Add("Cookie", cookieHeader); Stream memStream = new System.IO.MemoryStream(); byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n"); string formdataTemplate = "\r\n--" + boundary + "\r\nContent-Disposition: form-data; name=\"{0}\";\r\n\r\n{1}"; string formitem = string.Format(formdataTemplate, "headline", "image-name"); byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem); memStream.Write(formitembytes, 0, formitembytes.Length); memStream.Write(boundarybytes, 0, boundarybytes.Length); string headerTemplate = "\r\nContent-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: application/octet-stream\r\n\r\n"; string header = string.Format(headerTemplate, "userfile", "path-to-the-local-file"); byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header); memStream.Write(headerbytes, 0, headerbytes.Length); FileStream fileStream = new FileStream("path-to-the-local-file", FileMode.Open, FileAccess.Read); byte[] buffer = new byte[1024]; int bytesRead = 0; while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0) { memStream.Write(buffer, 0, bytesRead); } memStream.Write(boundarybytes, 0, boundarybytes.Length); fileStream.Close(); httpWebRequest2.ContentLength = memStream.Length; Stream requestStream = httpWebRequest2.GetRequestStream(); memStream.Position = 0; byte[] tempBuffer = new byte[memStream.Length]; memStream.Read(tempBuffer, 0, tempBuffer.Length); memStream.Close(); requestStream.Write(tempBuffer, 0, tempBuffer.Length); requestStream.Close(); WebResponse webResponse2 = httpWebRequest2.GetResponse(); Stream stream2 = webResponse2.GetResponseStream(); StreamReader reader2 = new StreamReader(stream2); Console.WriteLine(reader2.ReadToEnd()); webResponse2.Close(); httpWebRequest2 = null; webResponse2 = null; 这里也是PHP：（ http://dl.dropbox.com/u/3149888/index.php ）和（ http://dl.dropbox.com/u/3149888/new_image.php ）
必填字段是标题和用户文件，所以我无法弄清楚错误的位置，正如右边发送的格式。 我猜测发送到表单的八位字节流有问题。 也许这是一个我无法追查的愚蠢错误，无论如何，如果你能帮助我，那将意味着很多。
谢谢，
所以Martin帮助我在这里，我能够对上面的代码进行重要更改，以使其正常工作。 Content-Type必须更改为image / jpeg。 我还使用C＃Image类型发送图像流。
还要注意Stream格式，因为它不必包含额外的空格或新行。
这是改变的部分：
string formUrl = "http://localhost/pixelpost/admin/index.php?x=login"; string formParams = string.Format("user={0}&password={1}", "username", "password"); string cookieHeader; HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(formUrl); req.ContentType = "application/x-www-form-urlencoded"; req.Method = "POST"; req.AllowAutoRedirect = false; byte[] bytes = Encoding.ASCII.GetBytes(formParams); req.ContentLength = bytes.Length; using (Stream os = req.GetRequestStream()) { os.Write(bytes, 0, bytes.Length); } HttpWebResponse resp = (HttpWebResponse)req.GetResponse(); cookieHeader = resp.Headers["Set-Cookie"]; string pageSource; using (StreamReader sr = new StreamReader(resp.GetResponseStream())) { pageSource = sr.ReadToEnd(); } string getUrl = "http://localhost/pixelpost/admin/index.php"; HttpWebRequest getRequest = (HttpWebRequest)HttpWebRequest.Create(getUrl); getRequest.Headers.Add("Cookie", cookieHeader); HttpWebResponse getResponse = (HttpWebResponse)getRequest.GetResponse(); using (StreamReader sr = new StreamReader(getResponse.GetResponseStream())) { pageSource = sr.ReadToEnd(); } long length = 0; string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x"); HttpWebRequest httpWebRequest2 = (HttpWebRequest)WebRequest.Create("http://localhost/pixelpost/admin/index.php?x=save"); httpWebRequest2.ContentType = "multipart/form-data; boundary=" + boundary; httpWebRequest2.Method = "POST"; httpWebRequest2.AllowAutoRedirect = false; httpWebRequest2.KeepAlive = false; httpWebRequest2.Credentials = System.Net.CredentialCache.DefaultCredentials; httpWebRequest2.Headers.Add("Cookie", cookieHeader); Stream memStream = new System.IO.MemoryStream(); byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary); string headerTemplate = "\r\n--" + boundary + "\r\nContent-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: image/jpeg\r\n\r\n"; string header = string.Format(headerTemplate, "userfile", "Sunset.jpg"); byte[] headerbytes = System.Text.Encoding.ASCII.GetBytes(header); memStream.Write(headerbytes, 0, headerbytes.Length); Image img = null; img = Image.FromFile("C:/Documents and Settings/Dorin Cucicov/My Documents/My Pictures/Sunset.jpg", true); img.Save(memStream, System.Drawing.Imaging.ImageFormat.Jpeg); memStream.Write(boundarybytes, 0, boundarybytes.Length); string formdataTemplate = "\r\nContent-Disposition: form-data; name=\"{0}\";\r\n\r\n{1}"; string formitem = string.Format(formdataTemplate, "headline", "Sunset"); byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem); memStream.Write(formitembytes, 0, formitembytes.Length); memStream.Write(boundarybytes, 0, boundarybytes.Length); httpWebRequest2.ContentLength = memStream.Length; Stream requestStream = httpWebRequest2.GetRequestStream(); memStream.Position = 0; byte[] tempBuffer = new byte[memStream.Length]; memStream.Read(tempBuffer, 0, tempBuffer.Length); memStream.Close(); requestStream.Write(tempBuffer, 0, tempBuffer.Length); requestStream.Close(); WebResponse webResponse2 = httpWebRequest2.GetResponse(); Stream stream2 = webResponse2.GetResponseStream(); StreamReader reader2 = new StreamReader(stream2); Console.WriteLine(reader2.ReadToEnd()); webResponse2.Close(); httpWebRequest2 = null; webResponse2 = null;
再次感谢大家回答或只是阅读。