SmtpClient.Port Property


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Gets or sets the port used for SMTP transactions.

Namespace:   System.Net.Mail
Assembly:  System (in System.dll)

public int Port { get; set; }

Property Value

Type: System.Int32

An Int32 that contains the port number on the SMTP host. The default value is 25.

Exception Condition

The value specified for a set operation is less than or equal to zero.


You cannot change the value of this property when an email is being sent.

The value of the Port property can also be set using constructors or the application or machine configuration file. For more information about using configuration files, see <mailSettings> Element (Network Settings). If information is specified using this property, this information overrides the configuration file settings.

The following code example demonstrates sending an e-mail message by using the host and port specified in an application configuration file.

public static void CreateTestMessage4(string server)
	MailAddress from = new MailAddress("");
	MailAddress to = new MailAddress("");
	MailMessage message = new MailMessage(from, to);
	message.Subject = "Using the SmtpClient class.";
	message.Body = @"Using this feature, you can send an e-mail message from an application very easily.";
	SmtpClient client = new SmtpClient(server);
	Console.WriteLine("Sending an e-mail message to {0} by using SMTP host {1} port {2}.",
		 to.ToString(), client.Host, client.Port);

    try {
	catch (Exception ex) {
	  Console.WriteLine("Exception caught in CreateTestMessage4(): {0}", 
                  ex.ToString() );			  


to set the Port property. Associated enumeration: SmtpAccess.ConnectToUnrestrictedPort.

.NET Framework
Available since 2.0
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