multipart/form-data - Multipart MIME in Web API with form data

MIMEAttachment.cs

public async Task<object> Post()
        {
            //First check if request is Multipart Content
            if (!Request.Content.IsMimeMultipartContent())
            {
                return "Nope. Not this one.";
            }
            else
            {
                //The attachment type
                var AttachmentTypeIdNo = "";
                //The path to store the file
                var diskFolderPath = @"\Attachments\Images\";
                //Make an object of your defined class for the Form Data
                var myClassInstance = new MyClass();
                //Get all of the properties of your class
                var myClassProperties = myClassInstance.GetType().GetProperties();
                //Define the valid keys here so later a check will validate the form data not to be out of the context.
                var requestKeys = new List<string>();
                //The filenames that have been saved so far
                var fileNames = new List<string>();

                //Add all of the properties as keys
                foreach (var item in myClassProperties)
                {
                    requestKeys.Add(item.Name);
                }

                //Call these method to get all of the attachments
                var provider = new MultipartFormDataStreamProvider(HostingEnvironment.MapPath("~/App_Data"));

                await Request.Content.ReadAsMultipartAsync(provider);

                //We get those keys which we passed when making the post call. The keys from the Form [Form Data]
                //There will be one value for each key.
                foreach (var key in provider.FormData.AllKeys)
                {
                    //If the provided keys are not in the structure then return an error.
                    if (!requestKeys.Contains(key))
                    {
                        return "The form input are out of the defined class properties.";
                    }

                    if (key == "AttachmentTypeId")
                    {
                        AttachmentTypeIdNo = provider.FormData.GetValues(key)[0];
                    }
                }

                //Run a loop for all of the uploads/attachments
                foreach (MultipartFileData fileData in provider.FileData)
                {
                    //Some checks for names and all
                    string fileName = "";
                    if (string.IsNullOrEmpty(fileData.Headers.ContentDisposition.FileName))
                    {
                        fileName = Guid.NewGuid().ToString();
                    }
                    fileName = fileData.Headers.ContentDisposition.FileName;
                    if (fileName.StartsWith("\"") && fileName.EndsWith("\""))
                    {
                        fileName = fileName.Trim('"');
                    }
                    if (fileName.Contains(@"/") || fileName.Contains(@"\"))
                    {
                        fileName = Path.GetFileName(fileName);
                    }

                    fileName = (AttachmentTypeIdNo == "1" ? "attachment.jpg" : "attachment.mp4");

                    var newFileName = Path.Combine(HostingEnvironment.MapPath("~" + diskFolderPath), fileName);

                    var fileInfo = new FileInfo(newFileName);

                    if (!Directory.Exists(fileInfo.Directory.FullName))
                    {
                        Directory.CreateDirectory(fileInfo.Directory.FullName);
                    }
                    try
                    {
                        File.Copy(fileData.LocalFileName, newFileName);
                    }
                    catch (Exception)
                    {
                        return "Something wrong with attachment"
                    }


                    fileNames.Add(fileName);
                }
                //Do your SQL Server part over here
            }
}