/// <summary>
/// Create an file attachment for the specific file path
/// </summary>
/// <param name="filePath">Attachment file path</param>
/// <param name="attachmentFileName">Attachment file name</param>
/// <returns>A leaf-node MIME part that contains an attachment.</returns>
protected MimePart CreateMimeAttachment(string filePath, string attachmentFileName = null)
{
if (string.IsNullOrWhiteSpace(filePath))
{
throw new ArgumentNullException(nameof(filePath));
}
if (string.IsNullOrWhiteSpace(attachmentFileName))
{
attachmentFileName = Path.GetFileName(filePath);
}
return(CreateMimeAttachment(
attachmentFileName,
_fileProvider.ReadAllBytes(filePath),
_fileProvider.GetCreationTime(filePath),
_fileProvider.GetLastWriteTime(filePath),
_fileProvider.GetLastAccessTime(filePath)));
}