Upload File using RestClient as multipart/form-data in c#

Question

I am trying to upload files from the c# class using restClient (RestSharp) request. I am creating Method.POST method and add one Audio file to this request As multipart/form-data.

Server throws an exception when I execute the request.

Exception :

 System.ArgumentNullException: Value cannot be null.
 Parameter name: value
 at System.Enum.TryParseEnum(Type enumType, String value, Boolean ignoreCase, EnumResult& parseResult)
 at System.Enum.Parse(Type enumType, String value, Boolean ignoreCase)
 at Groove.Libraries.Helper.EnumHelper.ParseEnum[T](String value) in D:\project\Groove\Web\Groove\Libraries\Helper\EnumHelper.cs:line 47
 at Groove.Controllers.Api.DocumentController. 
 <PostDocumentUpload>d__5.MoveNext()

RestClient Request Code :

string api_url = "http://localhost:57997/";
var fullFileName = "Adios.mp3";
var filepath = @"C:\Users\Admin\Desktop\Adios.mp3";

RestClient client = new RestClient(ApiModel.api_url);

var request = new RestRequest("api/document", Method.POST);
request.AddFile(Path.GetFileNameWithoutExtension(fullFileName), filepath);
request.AddHeader("Content-Type", "multipart/form-data");
request.AddParameter("ReferenceType",28,ParameterType.RequestBody);
IRestResponse response = client.Execute(request);

Server Code :

public async Task<object> PostDocumentUpload()
    {
        try
        {
            // Make temp physical path where file to be saved
            var tempPath =
                HttpContext.Current.Server.MapPath(string.Format("{0}/{1}", Constants.MediaResourceFolder,
                    Constants.MediaResorceTempFolder));

            // Check temporary path is exist or not, if not then create temporary folder
            if (!Directory.Exists(tempPath))
            {
                Directory.CreateDirectory(tempPath);
            }

            // Create object of MyMultipartFormDataStreamProvider class
            var stream = new MultipartHelper(tempPath);

            // Save file at temp path
            await RequestContext.Request.Content.ReadAsMultipartAsync(stream);

            // Exception throw from Here,
            ReferenceType referenceType = EnumHelper.ParseEnum<ReferenceType>(stream.FormData["ReferenceType"]);
           // -------------other code     
        }
        catch (Exception ex)
        {
            return FailureResponse(ex);
        }

I guess problem is that stream.FormData["ReferenceType"] is not set correctly from request.

I don't want change the server code. because it working fine when you call from postman or browser.

Can somebody pls help? Thanks

Answer 1

I found the solution by just changing the few codes.

Updated Code :

       var request = new RestRequest("api/document", Method.POST);

        request.AddFile(Path.GetFileNameWithoutExtension(fullFileName), filepath);
        request.AddParameter("ReferenceType", ReferenceType.ToString());
        request.AddParameter("RefId", StudioEventEntryId.ToString());

        request.AlwaysMultipartFormData = true;

        IRestResponse response = client.Execute(request);