ASP .NET Web API

Question

This function is working for images, but i'm stucked at the point to use it for pdf, audio and video also.
I am receiving data in base64 format in asp.net web API and have to save it in folders and file name in database.

 

 

public static String LoadBase64(string base64File)
        {
            try
            {
                if (!string.IsNullOrEmpty(base64File))
                {
                    String path = HttpContext.Current.Server.MapPath("~/Images");
                    var fileName = DateTime.Now.ToFileTime() + ".jpg";
                    string imgPath = Path.Combine(path, fileName);
                    byte[] imageBytes = Convert.FromBase64String(base64File);
                    MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length);
                    ms.Write(imageBytes, 0, imageBytes.Length);
                    System.Drawing.Image image = System.Drawing.Image.FromStream(ms, true);
                    image.Save(imgPath, System.Drawing.Imaging.ImageFormat.Jpeg);
                    return fileName;
                }
                else
                {
                    return "Null";
                }
            }
            catch (Exception ex)
            {
                return (ex.Message);
            }
        }