Attachment Class

Definition

Namespace:

System.Net.Mail

Assembly:

System.Net.Mail.dll

Source:

Attachment.cs

Represents an attachment to an email.

public ref class Attachment : System::Net::Mail::AttachmentBase

public class Attachment : System.Net.Mail.AttachmentBase

type Attachment = class
    inherit AttachmentBase

Public Class Attachment
Inherits AttachmentBase

Inheritance

Object

AttachmentBase

Attachment

Examples

The following code example demonstrates attaching a file to an email message.

static void CreateMessageWithAttachment( String^ server )
{
   
   // Specify the file to be attached and sent.
   // This example assumes that a file named Data.xls exists in the
   // current working directory.
   String^ file = L"data.xls";
   
   // Create a message and set up the recipients.
   MailMessage^ message = gcnew MailMessage( L"jane@contoso.com",L"ben@contoso.com",L"Quarterly data report.",L"See the attached spreadsheet." );
   
   // Create  the file attachment for this email message.
   Attachment^ data = gcnew Attachment(file, MediaTypeNames::Application::Octet);
   
   // Add time stamp information for the file.
   ContentDisposition^ disposition = data->ContentDisposition;
   disposition->CreationDate = System::IO::File::GetCreationTime( file );
   disposition->ModificationDate = System::IO::File::GetLastWriteTime( file );
   disposition->ReadDate = System::IO::File::GetLastAccessTime( file );
   
   // Add the file attachment to this email message.
   message->Attachments->Add( data );
   
   //Send the message.
   SmtpClient^ client = gcnew SmtpClient( server );
   
   // Add credentials if the SMTP server requires them.
   client->Credentials = CredentialCache::DefaultNetworkCredentials;
   client->Send( message );
   
   // Display the values in the ContentDisposition for the attachment.
   ContentDisposition^ cd = data->ContentDisposition;
   Console::WriteLine( L"Content disposition" );
   Console::WriteLine( cd );
   Console::WriteLine( L"File {0}", cd->FileName );
   Console::WriteLine( L"Size {0}", cd->Size );
   Console::WriteLine( L"Creation {0}", cd->CreationDate );
   Console::WriteLine( L"Modification {0}", cd->ModificationDate );
   Console::WriteLine( L"Read {0}", cd->ReadDate );
   Console::WriteLine( L"Inline {0}", cd->Inline );
   Console::WriteLine( L"Parameters: {0}", cd->Parameters->Count );
   IEnumerator^ myEnum1 = cd->Parameters->GetEnumerator();
   while ( myEnum1->MoveNext() )
   {
      DictionaryEntry^ d = safe_cast<DictionaryEntry^>(myEnum1->Current);
      Console::WriteLine( L"{0} = {1}", d->Key, d->Value );
   }

   data->~Attachment();
   client->~SmtpClient();
}

public static void CreateMessageWithAttachment(string server)
{
    // Specify the file to be attached and sent.
    // This example assumes that a file named Data.xls exists in the
    // current working directory.
    string file = "data.xls";
    // Create a message and set up the recipients.
    MailMessage message = new MailMessage(
        "jane@contoso.com",
        "ben@contoso.com",
        "Quarterly data report.",
        "See the attached spreadsheet.");

    // Create  the file attachment for this email message.
    Attachment data = new Attachment(file, MediaTypeNames.Application.Octet);
    // Add time stamp information for the file.
    ContentDisposition disposition = data.ContentDisposition;
    disposition.CreationDate = System.IO.File.GetCreationTime(file);
    disposition.ModificationDate = System.IO.File.GetLastWriteTime(file);
    disposition.ReadDate = System.IO.File.GetLastAccessTime(file);
    // Add the file attachment to this email message.
    message.Attachments.Add(data);

    //Send the message.
    SmtpClient client = new SmtpClient(server);
    // Add credentials if the SMTP server requires them.
    client.Credentials = CredentialCache.DefaultNetworkCredentials;

    try
    {
        client.Send(message);
    }
    catch (Exception ex)
    {
        Console.WriteLine("Exception caught in CreateMessageWithAttachment(): {0}",
            ex.ToString());
    }
    // Display the values in the ContentDisposition for the attachment.
    ContentDisposition cd = data.ContentDisposition;
    Console.WriteLine("Content disposition");
    Console.WriteLine(cd.ToString());
    Console.WriteLine("File {0}", cd.FileName);
    Console.WriteLine("Size {0}", cd.Size);
    Console.WriteLine("Creation {0}", cd.CreationDate);
    Console.WriteLine("Modification {0}", cd.ModificationDate);
    Console.WriteLine("Read {0}", cd.ReadDate);
    Console.WriteLine("Inline {0}", cd.Inline);
    Console.WriteLine("Parameters: {0}", cd.Parameters.Count);
    foreach (DictionaryEntry d in cd.Parameters)
    {
        Console.WriteLine("{0} = {1}", d.Key, d.Value);
    }
    data.Dispose();
}

Remarks

The Attachment class is used with the MailMessage class. All messages include a Body, which contains the content of the message. In addition to the body, you might want to send additional files. These are sent as attachments and are represented as Attachment instances. To add an attachment to a mail message, add it to the MailMessage.Attachments collection.

Attachment content can be a String, Stream, or file name. You can specify the content in an attachment by using any of the Attachment constructors.

The MIME Content-Type header information for the attachment is represented by the ContentType property. The Content-Type header specifies the media type and subtype and any associated parameters. Use ContentType to get the instance associated with an attachment.

The MIME Content-Disposition header is represented by the ContentDisposition property. The Content-Disposition header specifies the presentation and file time stamps for an attachment. A Content-Disposition header is sent only if the attachment is a file. Use the ContentDisposition property to get the instance associated with an attachment.

The MIME Content-Transfer-Encoding header is represented by the TransferEncoding property.

Constructors

Attachment(Stream, ContentType)	Initializes a new instance of the Attachment class with the specified stream and content type.
Attachment(Stream, String)	Initializes a new instance of the Attachment class with the specified stream and name.
Attachment(Stream, String, String)	Initializes a new instance of the Attachment class with the specified stream, name, and MIME type information.
Attachment(String)	Initializes a new instance of the Attachment class with the specified content string.
Attachment(String, ContentType)	Initializes a new instance of the Attachment class with the specified content string and ContentType.
Attachment(String, String)	Initializes a new instance of the Attachment class with the specified content string and MIME type information.

Properties

ContentDisposition	Gets the MIME content disposition for this attachment.
ContentId	Gets or sets the MIME content ID for this attachment. (Inherited from AttachmentBase)
ContentStream	Gets the content stream of this attachment. (Inherited from AttachmentBase)
ContentType	Gets the content type of this attachment. (Inherited from AttachmentBase)
Name	Gets or sets the MIME content type name value in the content type associated with this attachment.
NameEncoding	Specifies the encoding for the AttachmentName.
TransferEncoding	Gets or sets the encoding of this attachment. (Inherited from AttachmentBase)

Methods

CreateAttachmentFromString(String, ContentType)	Creates a mail attachment using the content from the specified string, and the specified ContentType.
CreateAttachmentFromString(String, String)	Creates a mail attachment using the content from the specified string, and the specified MIME content type name.
CreateAttachmentFromString(String, String, Encoding, String)	Creates a mail attachment using the content from the specified string, the specified MIME content type name, character encoding, and MIME header information for the attachment.
Dispose()	Releases the resources used by the AttachmentBase. (Inherited from AttachmentBase)
Dispose(Boolean)	Releases the unmanaged resources used by the AttachmentBase and optionally releases the managed resources. (Inherited from AttachmentBase)
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)