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ContentType.Boundary Property

  • Reference

Definition

Namespace:
System.Net.Mime
Assembly:
System.Net.Mail.dll
Assembly:
System.dll
Assembly:
netstandard.dll
Source:
ContentType.cs
Source:
ContentType.cs
Source:
ContentType.cs

Gets or sets the value of the boundary parameter included in the Content-Type header represented by this instance.

public:
 property System::String ^ Boundary { System::String ^ get(); void set(System::String ^ value); };
public string? Boundary { get; set; }
public string Boundary { get; set; }
member this.Boundary : string with get, set
Public Property Boundary As String

Property Value

String

A String that contains the value associated with the boundary parameter.

Examples

The following code example displays the value of the Boundary property.

static void CreateMessageWithMultipleViews( String^ server, String^ recipients )
{
   
   // Create a message and set up the recipients.
   MailMessage^ message = gcnew MailMessage( L"jane@contoso.com",recipients,L"This email message has multiple views.",L"This is some plain text." );
   
   // Construct the alternate body as HTML.
   String^ body = L"<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 Transitional//EN\">";
   body = String::Concat( body, L"<HTML><HEAD><META http-equiv=Content-Type content=\"text/html; charset=iso-8859-1\">" );
   body = String::Concat( body, L"</HEAD><BODY><DIV><FONT face=Arial color=#ff0000 size=2>this is some HTML text" );
   body = String::Concat( body, L"</FONT></DIV></BODY></HTML>" );
   
   // Add the alternate body to the message.
   AlternateView^ alternate = AlternateView::CreateAlternateViewFromString(body);
   message->AlternateViews->Add(alternate);

   // Send the message.
   SmtpClient^ client = gcnew SmtpClient( server );
   client->Credentials = CredentialCache::DefaultNetworkCredentials;
   client->Send( message );
   
   // Display the values in the ContentType for the attachment.
   ContentType^ c = alternate->ContentType;
   Console::WriteLine( L"Content type" );
   Console::WriteLine( c );
   Console::WriteLine( L"Boundary {0}", c->Boundary );
   Console::WriteLine( L"CharSet {0}", c->CharSet );
   Console::WriteLine( L"MediaType {0}", c->MediaType );
   Console::WriteLine( L"Name {0}", c->Name );
   Console::WriteLine( L"Parameters: {0}", c->Parameters->Count );
   IEnumerator^ myEnum = c->Parameters->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      DictionaryEntry^ d = safe_cast<DictionaryEntry^>(myEnum->Current);
      Console::WriteLine( L"{0} = {1}", d->Key, d->Value );
   }

   Console::WriteLine();
   alternate->~AlternateView();
}

public static void CreateMessageWithMultipleViews(string server, string recipients)
{
    // Create a message and set up the recipients.
    MailMessage message = new MailMessage(
        "jane@contoso.com",
        recipients,
        "This email message has multiple views.",
        "This is some plain text.");

    // Construct the alternate body as HTML.
    string body = "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 Transitional//EN\">";
    body += "<HTML><HEAD><META http-equiv=Content-Type content=\"text/html; charset=iso-8859-1\">";
    body += "</HEAD><BODY><DIV><FONT face=Arial color=#ff0000 size=2>this is some HTML text";
    body += "</FONT></DIV></BODY></HTML>";

    ContentType mimeType = new System.Net.Mime.ContentType("text/html");
    // Add the alternate body to the message.

    AlternateView alternate = AlternateView.CreateAlternateViewFromString(body, mimeType);
    message.AlternateViews.Add(alternate);

    // Send the message.
    SmtpClient client = new SmtpClient(server);
    client.Credentials = CredentialCache.DefaultNetworkCredentials;

    try
    {
        client.Send(message);
    }
    catch (Exception ex)
    {
        Console.WriteLine("Exception caught in CreateMessageWithMultipleViews(): {0}",
            ex.ToString());
    }
    // Display the values in the ContentType for the attachment.
    ContentType c = alternate.ContentType;
    Console.WriteLine("Content type");
    Console.WriteLine(c.ToString());
    Console.WriteLine("Boundary {0}", c.Boundary);
    Console.WriteLine("CharSet {0}", c.CharSet);
    Console.WriteLine("MediaType {0}", c.MediaType);
    Console.WriteLine("Name {0}", c.Name);
    Console.WriteLine("Parameters: {0}", c.Parameters.Count);
    foreach (DictionaryEntry d in c.Parameters)
    {
        Console.WriteLine("{0} = {1}", d.Key, d.Value);
    }
    Console.WriteLine();
    alternate.Dispose();
}

Remarks

In the following example of a Content-Type header, the value of the Boundary parameter is "-----boundary---0".

content-type: multipart/mixed; boundary=-----boundary---0

Set this property to null or String.Empty to remove the boundary information from the header.

The syntax of the Content-Type header is described in RFC 2045 Section 5.1. An in-depth discussion of the boundary parameter is contained in RFC 2046 Section 5.1.1. These RFCs are available at https://www.ietf.org.

Applies to