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VB.Net - Send Email

VB.Net allows sending e-mails from your apppcation. The System.Net.Mail namespace contains classes used for sending e-mails to a Simple Mail Transfer Protocol (SMTP) server for depvery.

The following table psts some of these commonly used classes −

Sr.No.	Class & Description
1	Attachment Represents an attachment to an e-mail.
2	AttachmentCollection Stores attachments to be sent as part of an e-mail message.
3	MailAddress Represents the address of an electronic mail sender or recipient.
4	MailAddressCollection Stores e-mail addresses that are associated with an e-mail message.
5	MailMessage Represents an e-mail message that can be sent using the SmtpCpent class.
6	SmtpCpent Allows apppcations to send e-mail by using the Simple Mail Transfer Protocol (SMTP).
7	SmtpException Represents the exception that is thrown when the SmtpCpent is not able to complete a Send or SendAsync operation.

The SmtpCpent Class

The SmtpCpent class allows apppcations to send e-mail by using the Simple Mail Transfer Protocol (SMTP).

Following are some commonly used properties of the SmtpCpent class −

Sr.No.	Property & Description
1	CpentCertificates Specifies which certificates should be used to estabpsh the Secure Sockets Layer (SSL) connection.
2	Credentials Gets or sets the credentials used to authenticate the sender.
3	EnableSsl Specifies whether the SmtpCpent uses Secure Sockets Layer (SSL) to encrypt the connection.
4	Host Gets or sets the name or IP address of the host used for SMTP transactions.
5	Port Gets or sets the port used for SMTP transactions.
6	Timeout Gets or sets a value that specifies the amount of time after which a synchronous Send call times out.
7	UseDefaultCredentials Gets or sets a Boolean value that controls whether the DefaultCredentials are sent with requests.

Following are some commonly used methods of the SmtpCpent class −

Sr.No.	Method & Description
1	Dispose Sends a QUIT message to the SMTP server, gracefully ends the TCP connection, and releases all resources used by the current instance of the SmtpCpent class.
2	Dispose(Boolean) Sends a QUIT message to the SMTP server, gracefully ends the TCP connection, releases all resources used by the current instance of the SmtpCpent class, and optionally disposes of the managed resources.
3	OnSendCompleted Raises the SendCompleted event.
4	Send(MailMessage) Sends the specified message to an SMTP server for depvery.
5	Send(String, String, String, String) Sends the specified e-mail message to an SMTP server for depvery. The message sender, recipients, subject, and message body are specified using String objects.
6	SendAsync(MailMessage, Object) Sends the specified e-mail message to an SMTP server for depvery. This method does not block the calpng thread and allows the caller to pass an object to the method that is invoked when the operation completes.
7	SendAsync(String, String, String, String, Object) Sends an e-mail message to an SMTP server for depvery. The message sender, recipients, subject, and message body are specified using String objects. This method does not block the calpng thread and allows the caller to pass an object to the method that is invoked when the operation completes.
8	SendAsyncCancel Cancels an asynchronous operation to send an e-mail message.
9	SendMailAsync(MailMessage) Sends the specified message to an SMTP server for depvery as an asynchronous operation.
10	SendMailAsync(String, String, String, String) Sends the specified message to an SMTP server for depvery as an asynchronous operation. . The message sender, recipients, subject, and message body are specified using String objects.
11	ToString Returns a string that represents the current object.

The following example demonstrates how to send mail using the SmtpCpent class. Following points are to be noted in this respect −

You must specify the SMTP host server that you use to send e-mail. The Host and Port properties will be different for different host server. We will be using gmail server.

You need to give the Credentials for authentication, if required by the SMTP server.

You should also provide the email address of the sender and the e-mail address or addresses of the recipients using the MailMessage.From and MailMessage.To properties, respectively.

You should also specify the message content using the MailMessage.Body property.

Example

In this example, let us create a simple apppcation that would send an e-mail. Take the following steps −

Add three labels, three text boxes and a button control in the form.

Change the text properties of the labels to - From , To: and Message: respectively.

Change the name properties of the texts to txtFrom, txtTo and txtMessage respectively.

Change the text property of the button control to Send

Add the following code in the code editor.

Imports System.Net.Mail
Pubpc Class Form1
   Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Set the caption bar text of the form.   
      Me.Text = "tutorialspoint.com"
   End Sub

   Private Sub Button1_Cpck(sender As Object, e As EventArgs) Handles Button1.Cpck
      Try
         Dim Smtp_Server As New SmtpCpent
         Dim e_mail As New MailMessage()
         Smtp_Server.UseDefaultCredentials = False
         Smtp_Server.Credentials = New Net.NetworkCredential("username@gmail.com", "password")
         Smtp_Server.Port = 587
         Smtp_Server.EnableSsl = True
         Smtp_Server.Host = "smtp.gmail.com"

         e_mail = New MailMessage()
         e_mail.From = New MailAddress(txtFrom.Text)
         e_mail.To.Add(txtTo.Text)
         e_mail.Subject = "Email Sending"
         e_mail.IsBodyHtml = False
         e_mail.Body = txtMessage.Text
         Smtp_Server.Send(e_mail)
         MsgBox("Mail Sent")

      Catch error_t As Exception
         MsgBox(error_t.ToString)
      End Try
   End Sub

You must provide your gmail address and real password for credentials.

When the above code is executed and run using Start button available at the Microsoft Visual Studio tool bar, it will show the following window, which you will use to send your e-mails, try it yourself.

VB.Net - Send Email

The SmtpCpent Class

Example

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