C# HttpWebRequest 上传文件 （调用ArcGIS Rest API上传SOE文件）

缘起

想做一个SOE自动上传的小工具，查了查相关的ArcGIS Rest API，使用C#中的HttpWebRequet实现，k看GitHub上别人用Python实现的很简单，自己用C#搞了一天了没搞明白，记录一下采坑的过程。

相关资料

1. ArcGIS Rest API Upload SOE：传送门
2. C# Upload File：参考链接1、参考链接2、
3. HttpClient实现方法：参考链接

PostMan测试

使用PostMan测试Form-data，参考链接

代码实现

• HttpWebRequest

  private bool UploadSoe(string userName, string password, string soeFilePath, string ip = "localhost", string port = "6080")
  {bool bIsSuccess = false;//构造请求参数string token = GetToken(userName, password, ip, port);string boundary = CreateFormDataBoundary();byte[] postDataBytes = null;using (var postStream = new MemoryStream()){//写入表单参数string formDataTemplate = "--{0}\r\nContent-Disposition: form-data; name=\"{1}\"\r\n\r\n{2}\r\n";string fromData1 = string.Format(formDataTemplate, boundary, "f", "json");var dataFormdataBytes1 = Encoding.UTF8.GetBytes(fromData1);string formData2 = string.Format(formDataTemplate, boundary, "token", token);var dataFormdataBytes2 = Encoding.UTF8.GetBytes(formData2);//写入文件头部信息string fileFormdataTemplate = "--{0}\r\nContent-Disposition: form-data; name=\"{1}\"; filename=\"{2}\"\r\nContent-Type: {3}\r\n\r\n";string soeFileName = System.IO.Path.GetFileName(soeFilePath);string fileHeader = string.Format(fileFormdataTemplate, boundary, "itemFile", soeFileName, "application/octet-stream");byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(fileHeader);//写入文件流byte[] fileBytes = null;using (FileStream fs = new FileStream(soeFilePath, FileMode.Open)){fileBytes = new byte[fs.Length];fs.Read(fileBytes, 0, fileBytes.Length);fs.Close();}//写入结尾string sEndBoundary = "\r\n--" + boundary + "--\r\n";var endBoundaryBytes = Encoding.UTF8.GetBytes(sEndBoundary);postStream.Write(dataFormdataBytes1, 0, dataFormdataBytes1.Length);postStream.Write(dataFormdataBytes2, 0, dataFormdataBytes2.Length);postStream.Write(headerbytes, 0, headerbytes.Length);postStream.Write(fileBytes, 0, fileBytes.Length);postStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);postStream.Position = 0;postDataBytes = new byte[postStream.Length];postStream.Read(postDataBytes, 0, postDataBytes.Length);postStream.Close(); }//创建Httphelper对象HttpHelper http = new HttpHelper();//创建Httphelper参数对象HttpItem item = new HttpItem(){URL = string.Format("http://{0}:{1}/arcgis/admin/uploads/upload", ip, port),Method = "POST",ContentType = string.Format("multipart/form-data; boundary={0}", boundary),PostDataType = Sys.PostDataType.Byte,PostdataByte = postDataBytes};//请求的返回值对象HttpResult result = http.GetHtml(item);if (result.StatusCode == System.Net.HttpStatusCode.OK){string html = result.Html;var jsonObj = JsonHelper.GetDynamicObjFromString(html);if (jsonObj.status.ToString() == "success"){bIsSuccess = true;}}return bIsSuccess;
  }private static string CreateFormDataBoundary()
  {return "----" + DateTime.Now.Ticks.ToString("x");
  }private string GetToken(string userName, string password, string ip = "localhost", string port = "6080")
  {//创建Httphelper对象HttpHelper http = new HttpHelper();//创建Httphelper参数对象HttpItem item = new HttpItem(){URL = string.Format("http://{0}:{1}/arcgis/admin/generateToken", ip, port),//URL     必需项    Method = "post",//URL     可选项 默认为Get   ContentType = "application/x-www-form-urlencoded",//返回类型    可选项有默认值Postdata = string.Format("username={0}&password={1}&client=requestip&expiration=90&f=json", userName, password),//Post要发送的数据};//请求的返回值对象HttpResult result = http.GetHtml(item);//从苏飞论坛或者Github获取，也可以自己用HttpWebRequest//获取请请求的Htmlstring html = result.Html;//获取请求的Cookievar jsonObj = JsonHelper.GetDynamicObjFromString(html);var token = jsonObj.token;return token.ToString();
  }
  

• HttpClient

  private async void UploadSoe1(string userName, string password, string soeFilePath, string ip = "localhost", string port = "6080")
  {string token = GetToken(userName, password, ip, port);string soeFileName = Path.GetFileName(soeFilePath);using (FileStream stream = new FileStream(soeFilePath, FileMode.Open))using (HttpClient client = new HttpClient()){MultipartFormDataContent content = new MultipartFormDataContent();content.Add(new StringContent("pjson"), "f");content.Add(new StringContent(token), "token");content.Add(new StreamContent(stream){Headers ={ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream")}}, "itemFile", soeFileName);string url = string.Format("http://{0}:{1}/arcgis/admin/uploads/upload", ip, port);var response = await client.PostAsync(url, content);string resultContent = await response.Content.ReadAsStringAsync();}}
  

采坑小记

使用HttpWebRequest时需要自行构造body，这块相比HttpClient麻烦一点，这块要注意构造请求体是字符串的顺序，依次往requestStream中写入

1. 构造boundary信息

   private static string CreateFormDataBoundary()
   {return "----" + DateTime.Now.Ticks.ToString("x");
   }
   

2. 构造请求参数的相关信息

   string formDataTemplate = "--{0}\r\nContent-Disposition: form-data; name=\"{1}\"\r\n\r\n{2}\r\n";
   string fromData1 = string.Format(formDataTemplate, boundary, "f", "json");
   var dataFormdataBytes1 = Encoding.UTF8.GetBytes(fromData1);
   

3. 构造上传文件的相关信息

   string fileFormdataTemplate = "--{0}\r\nContent-Disposition: form-data; name=\"{1}\"; filename=\"{2}\"\r\nContent-Type: {3}\r\n\r\n";
   string soeFileName = System.IO.Path.GetFileName(soeFilePath);
   string fileHeader = string.Format(fileFormdataTemplate, boundary, "itemFile", soeFileName, "application/octet-stream");	
   byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(fileHeader);
   

4. 添加换行

   byte[] bytes = Encoding.UTF8.GetBytes("\r\n");
   

5. 添加结尾信息

   string sEndBoundary = "--" + boundary + "--\r\n";
   var endBoundaryBytes = Encoding.UTF8.GetBytes(sEndBoundary);
   

最后依次写入：

  Stream requestStream = request.GetRequestStream();requestStream.Write(dataFormdataBytes1, 0, dataFormdataBytes1.Length);requestStream.Write(dataFormdataBytes2, 0, dataFormdataBytes2.Length);//这块我有两个参数，没有封装函数，直接重复代码写了两遍requestStream.Write(headerbytes, 0, headerbytes.Length);requestStream.Write(fileBytes, 0, fileBytes.Length);byte[] bytes = Encoding.UTF8.GetBytes("\r\n");requestStream.Write(bytes, 0, bytes.Length);requestStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);

总结

如果对.Net Framework的版本没有要求的话（可以使用4.5及以上版本）建议使用HttpClient实现，毕竟HTTPWebRequest是很久之前的类，调用起来构造比较麻烦。