Extensions.cs

using System;
using System.IO;
using System.Net.Mail;
using System.Text;
using S22.Imap;

namespace S22.Mail
{
  /// <summary>
  ///   Contains extension methods for the MailMessage class of the System.Net.Mail
  ///   namespace.
  /// </summary>
  public static class MailExtension
  {
    /// <summary>
    ///   Saves the MailMessage instance to the specified stream.
    /// </summary>
    /// <param name="m">Extension method for MailMessage class.</param>
    /// <param name="stream">
    ///   The stream the MailMessage data will be
    ///   written to.
    /// </param>
    /// <remarks>
    ///   The mail message is saved as plain text in MIME
    ///   format (known as .eml in many email clients)
    /// </remarks>
    public static void Save(this MailMessage m, Stream stream)
    {
      var bytes = Encoding.ASCII.GetBytes(m.ToMIME822());
      stream.Write(bytes, 0, bytes.Length);
    }

    /// <summary>
    ///   Saves the MailMessage instance to the specified file.
    /// </summary>
    /// <param name="m">Extension method for MailMessage class</param>
    /// <param name="name">
    ///   A relative or absolute path for the file the
    ///   MailMessage will be saved to.
    /// </param>
    /// <remarks>
    ///   The mail message is saved as plain text in MIME
    ///   format (known as .eml in many email clients)
    /// </remarks>
    public static void Save(this MailMessage m, string name)
    {
      using (var s = new FileStream(name, FileMode.Create))
        m.Save(s);
    }

    /// <summary>
    ///   Creates a MailMessage instance from the specified stream.
    /// </summary>
    /// <param name="stream">
    ///   The stream the MailMessage will be constructed
    ///   from.
    /// </param>
    /// <returns>An initialized MailMessage object</returns>
    public static MailMessage Load(Stream stream)
    {
      using (var r = new StreamReader(stream))
      {
        return MessageBuilder.FromMIME822(r.ReadToEnd());
      }
    }

    /// <summary>
    ///   Creates a MailMessage instance from the specified file (*.eml).
    /// </summary>
    /// <param name="name">
    ///   A relative or absolute path for the file the
    ///   MailMessage will be saved to.
    /// </param>
    /// <returns>An initialized MailMessage object</returns>
    public static MailMessage Load(string name)
    {
      using (var s = new FileStream(name, FileMode.Open))
        return Load(s);
    }

    /// <summary>
    ///   Saves the contents of the attachment to the specified file.
    /// </summary>
    /// <param name="attachment">Extension method for Attachment class</param>
    /// <param name="name">The file to save the attachment to.</param>
    /// <exception cref="IOException">
    ///   Thrown when an I/O error occurs during
    ///   the save operation. Use the InnerException property to obtain the exception that
    ///   led to the current exception.
    /// </exception>
    /// <remarks>
    ///   If the file does not exist, it will be created. If the file already
    ///   exists, it will be truncated and overwritten.
    /// </remarks>
    public static void SaveAs(this Attachment attachment, string name)
    {
      int count;
      var buffer = new byte[4096];
      var stream = attachment.ContentStream;
      try
      {
        using (var fs = new FileStream(name, FileMode.Create))
        {
          while ((count = stream.Read(buffer, 0, buffer.Length)) != 0)
            fs.Write(buffer, 0, count);
        }
      }
      catch (Exception e)
      {
        throw new IOException(e.Message, e);
      }
      finally
      {
        if (stream.CanSeek)
          stream.Seek(0, SeekOrigin.Begin);
      }
    }
  }
}