System.IO.FileInfo.Open C# (CSharp) Method

        public FileStream Open(FileMode mode)
        {
            return Open(mode, (mode == FileMode.Append ? FileAccess.Write : FileAccess.ReadWrite), FileShare.None);
        }

 public void SaveFile(string fileName, IList<Shape> shapes)
 {
     var fileInfo = new FileInfo(fileName);
     try
     {
         if (fileInfo.Exists)
         {
             using (var fileStream = fileInfo.Open(FileMode.Truncate, FileAccess.ReadWrite))
             {
                 SerializeAndSave(shapes, fileStream);
             }
         }
         else
         {
             using (var fileStream = fileInfo.Open(FileMode.CreateNew, FileAccess.ReadWrite))
             {
                 SerializeAndSave(shapes, fileStream);
             }
         }
     }
     catch (Exception exception)
     {
        ThrowMeaningfulException(exception, fileName);
     }
 }