Why do I need to Dispose a System.Net.Mail.MailMessage instance?

Question

What unmanaged resources does it allocates that needs to be disposed? Isn't it just a simple array of managed data? So why disposing?

Answer 1

A mail message has attachments -> attachments are Streams -> Streams are to be disposed.

Here is the decompiled Dispose method of MailMessage:

    protected virtual void Dispose(bool disposing)     {         if (disposing && !this.disposed)         {             this.disposed = true;             if (this.views != null)             {                 this.views.Dispose();             }             if (this.attachments != null)             {                 this.attachments.Dispose();             }             if (this.bodyView != null)             {                 this.bodyView.Dispose();             }         }     } 

As a general rule a class should implement IDisposable if any of its contained children implement it.