使用WebClient的POST值上传文件
我想使用WebClient类将文件上传到主机。 我还想传递一些应该显示在服务器部分（PHP）上的$ _POST数组中的值。 我想通过一个连接来做到这一点
我用了下面的代码
using (WebClient wc = new WebClient()) { wc.Encoding = Encoding.UTF8; NameValueCollection values = new NameValueCollection(); values.Add("client", "VIP"); values.Add("name", "John Doe"); wc.QueryString = values; // this displayes in $_GET byte[] ans= wc.UploadFile(address, dumpPath); } 如果我使用了QueryString属性，$ _GET数组中显示的值。但我想通过post方法发送它
内置任何内容都无法让您这样做。 我在博客上写了一篇你可以使用的扩展程序。 以下是相关课程：
public class UploadFile { public UploadFile() { ContentType = "application/octet-stream"; } public string Name { get; set; } public string Filename { get; set; } public string ContentType { get; set; } public Stream Stream { get; set; } } public byte[] UploadFiles(string address, IEnumerable files, NameValueCollection values) { var request = WebRequest.Create(address); request.Method = "POST"; var boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x", NumberFormatInfo.InvariantInfo); request.ContentType = "multipart/form-data; boundary=" + boundary; boundary = "--" + boundary; using (var requestStream = request.GetRequestStream()) { // Write the values foreach (string name in values.Keys) { var buffer = Encoding.ASCII.GetBytes(boundary + Environment.NewLine); requestStream.Write(buffer, 0, buffer.Length); buffer = Encoding.ASCII.GetBytes(string.Format("Content-Disposition: form-data; name=\"{0}\"{1}{1}", name, Environment.NewLine)); requestStream.Write(buffer, 0, buffer.Length); buffer = Encoding.UTF8.GetBytes(values[name] + Environment.NewLine); requestStream.Write(buffer, 0, buffer.Length); } // Write the files foreach (var file in files) { var buffer = Encoding.ASCII.GetBytes(boundary + Environment.NewLine); requestStream.Write(buffer, 0, buffer.Length); buffer = Encoding.UTF8.GetBytes(string.Format("Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"{2}", file.Name, file.Filename, Environment.NewLine)); requestStream.Write(buffer, 0, buffer.Length); buffer = Encoding.ASCII.GetBytes(string.Format("Content-Type: {0}{1}{1}", file.ContentType, Environment.NewLine)); requestStream.Write(buffer, 0, buffer.Length); file.Stream.CopyTo(requestStream); buffer = Encoding.ASCII.GetBytes(Environment.NewLine); requestStream.Write(buffer, 0, buffer.Length); } var boundaryBuffer = Encoding.ASCII.GetBytes(boundary + "--"); requestStream.Write(boundaryBuffer, 0, boundaryBuffer.Length); } using (var response = request.GetResponse()) using (var responseStream = response.GetResponseStream()) using (var stream = new MemoryStream()) { responseStream.CopyTo(stream); return stream.ToArray(); } }
现在你可以在你的应用程序中使用它：
using (var stream = File.Open(dumpPath, FileMode.Open)) { var files = new[] { new UploadFile { Name = "file", Filename = Path.GetFileName(dumpPath), ContentType = "text/plain", Stream = stream } }; var values = new NameValueCollection { { "client", "VIP" }, { "name", "John Doe" }, }; byte[] result = UploadFiles(address, files, values); }
现在在你的PHP脚本中你可以使用$_POST["client"] ， $_POST["name"]和$_FILES["file"] 。
如果有人想在进度报告的异步模式中使用@ darin-dimitrov的解决方案，那就是要走的路（对于.NET 4.0）：
public void UploadFileAsync(NameValueCollection values, Stream fileStream) { //to fire events on the calling thread _asyncOperation = AsyncOperationManager.CreateOperation(null); var ms = new MemoryStream(); //make a copy of the input stream in case sb uses disposable stream fileStream.CopyTo(ms); //you cannot set stream position often enough to zero ms.Position = 0; Task.Factory.StartNew(() => { try { const string contentType = "application/octet-stream"; var request = WebRequest.Create(_url); request.Method = "POST"; var boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x", NumberFormatInfo.InvariantInfo); request.ContentType = "multipart/form-data; boundary=" + boundary; boundary = "--" + boundary; var dataStream = new MemoryStream(); byte[] buffer; // Write the values foreach (string name in values.Keys) { buffer = Encoding.ASCII.GetBytes(boundary + Environment.NewLine); dataStream.Write(buffer, 0, buffer.Length); buffer = Encoding.ASCII.GetBytes(string.Format("Content-Disposition: form-data; name=\"{0}\"{1}{1}", name, Environment.NewLine)); dataStream.Write(buffer, 0, buffer.Length); buffer = Encoding.UTF8.GetBytes(values[name] + Environment.NewLine); dataStream.Write(buffer, 0, buffer.Length); } // Write the file buffer = Encoding.ASCII.GetBytes(boundary + Environment.NewLine); dataStream.Write(buffer, 0, buffer.Length); buffer = Encoding.UTF8.GetBytes($"Content-Disposition: form-data; name=\"file\"; filename=\"file\"{Environment.NewLine}"); dataStream.Write(buffer, 0, buffer.Length); buffer = Encoding.ASCII.GetBytes(string.Format("Content-Type: {0}{1}{1}", contentType, Environment.NewLine)); dataStream.Write(buffer, 0, buffer.Length); ms.CopyTo(dataStream); buffer = Encoding.ASCII.GetBytes(Environment.NewLine); dataStream.Write(buffer, 0, buffer.Length); buffer = Encoding.ASCII.GetBytes(boundary + "--"); dataStream.Write(buffer, 0, buffer.Length); dataStream.Position = 0; //IMPORTANT: set content length to directly write to network socket request.ContentLength = dataStream.Length; var requestStream = request.GetRequestStream(); //Write data in chunks and report progress var size = dataStream.Length; const int chunkSize = 64 * 1024; buffer = new byte[chunkSize]; long bytesSent = 0; int readBytes; while ((readBytes = dataStream.Read(buffer, 0, buffer.Length)) > 0) { requestStream.Write(buffer, 0, readBytes); bytesSent += readBytes; var status = "Uploading... " + bytesSent / 1024 + "KB of " + size / 1024 + "KB"; var percentage = Tools.Clamp(Convert.ToInt32(100 * bytesSent / size), 0, 100); OnFileUploaderProgressChanged(new FileUploaderProgessChangedEventArgs(status, percentage)); } //get response using (var response = request.GetResponse()) using (var responseStream = response.GetResponseStream()) using (var stream = new MemoryStream()) { // ReSharper disable once PossibleNullReferenceException - exception would get catched anyway responseStream.CopyTo(stream); var result = Encoding.Default.GetString(stream.ToArray()); OnFileUploaderCompleted(result == string.Empty ? new FileUploaderCompletedEventArgs(FileUploaderCompletedResult.Failed) : new FileUploaderCompletedEventArgs(FileUploaderCompletedResult.Ok)); } } catch (Exception) { OnFileUploaderCompleted(new FileUploaderCompletedEventArgs(FileUploaderCompletedResult.Failed)); } }, CancellationToken.None, TaskCreationOptions.LongRunning, TaskScheduler.Default); }