WebAPI通过multipart/form-data方式同时上传文件以及数据（含HttpClient上传Demo）

/// <summary> /// 获得文件集合对应的ByteArrayContent集合 /// </summary> /// <param name="files"></param> /// <returns></returns> private List<ByteArrayContent> GetFileByteArrayContent(HashSet<string> files) { List<ByteArrayContent> list = new List<ByteArrayContent>(); foreach (var file in files) { var fileContent = new ByteArrayContent(File.ReadAllBytes(file)); fileContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment") { FileName = Path.GetFileName(file) }; list.Add(fileContent); } return list; } /// <summary> /// 获得键值集合对应的ByteArrayContent集合 /// </summary> /// <param name="collection"></param> /// <returns></returns> private List<ByteArrayContent> GetFormDataByteArrayContent(NameValueCollection collection) { List<ByteArrayContent> list = new List<ByteArrayContent>(); foreach (var key in collection.AllKeys) { var dataContent = new ByteArrayContent(Encoding.UTF8.GetBytes(collection[key])); dataContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment") { Name = key }; list.Add(dataContent); } return list; }

using (HttpClient client = new HttpClient()) { client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("text/" + this.cmbResponseContentType.Text.ToLower()));//设定要响应的数据格式 using (var content = new MultipartFormDataContent())//表明是通过multipart/form-data的方式上传数据 { var formDatas = this.GetFormDataByteArrayContent(this.GetNameValueCollection(this.gv_FormData));//获得键值集合对应的ByteArrayContent集合 var files = this.GetFileByteArrayContent(this.GetHashSet(this.gv_File));//获得文件集合对应的ByteArrayContent集合 Action<List<ByteArrayContent>> act = (dataContents) => {//声明1个拜托，该拜托的作用就是将ByteArrayContent集合加入到MultipartFormDataContent中 foreach (var byteArrayContent in dataContents) { content.Add(byteArrayContent); } }; act(formDatas);//履行act act(files);//履行act try { var result = client.PostAsync(this.txtUrl.Text, content).Result;//post要求 this.txtResponse.Text = result.Content.ReadAsStringAsync().Result;//将响应结果显示在文本框内 } catch (Exception ex) { this.txtResponse.Text = ex.ToString();//将异常信息显示在文本框内 } } }

[HttpPost] public async Task<Dictionary<string, string>> Post(int id = 0) { if (!Request.Content.IsMimeMultipartContent()) { throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType); } Dictionary<string, string> dic = new Dictionary<string, string>(); string root = HttpContext.Current.Server.MapPath("~/App_Data");//指定要将文件存入的服务器物理位置 var provider = new MultipartFormDataStreamProvider(root); try { // Read the form data. await Request.Content.ReadAsMultipartAsync(provider); // This illustrates how to get the file names. foreach (MultipartFileData file in provider.FileData) {//接收文件 Trace.WriteLine(file.Headers.ContentDisposition.FileName);//获得上传文件实际的文件名 Trace.WriteLine("Server file path: " + file.LocalFileName);//获得上传文件在服务上默许的文件名 }//TODO:这样做直接就将文件存到了指定目录下，暂时不知道如何实现只接收文件数据流但其实不保存至服务器的目录下，由开发自行指定如何存储，比如通过服务存到图片服务器 foreach (var key in provider.FormData.AllKeys) {//接收FormData dic.Add(key, provider.FormData[key]); } } catch { throw; } return dic; }