How can I send an email with my vb.net code? - asp.net

Question

I am using asp.net / vb.net. I want to send an email. My code does not send an email as it is. I am wondering what I am doing wrong here.
I created a file called email.text that holds the email template. The rest of the code to send the email is below. I removed personal information from my code.
I setup the SMTP connection as such:
Private SMTPClientConnection As SmtpClient
Sub New()
SMTPClientConnection = New SmtpClient
SMTPClientConnection.Host = "HOSTHERE"
SMTPClientConnection.Port = PORTHERE
SMTPClientConnection.DeliveryMethod = SmtpDeliveryMethod.Network
End Sub
Then I created a function to send the email:
Private Shared Function SendEmail(ByVal emailUser As String, ByVal bodyMessage As List(Of String), ByVal priority As MailPriority) As Boolean
Dim functionReturnValue As Boolean = False
Try
If Not String.IsNullOrWhiteSpace(emailUser) Then
If Regex.IsMatch(emailUser, "^([a-zA-Z0-9]+([\.+_-][a-zA-Z0-9]+)*)#(([a-zA-Z0-9]+((\.|[-]{1,2})[a-zA-Z0-9]+)*)\.[a-zA-Z]{2,6})$") Then
Using SMTPClientConnection
Dim smtpMessage As MailMessage = New MailMessage()
Dim _with1 = smtpMessage
_with1.[To].Add(New MailAddress(emailUser))
_with1.From = New MailAddress("Test Email" & " <email#email.com>")
_with1.ReplyToList.Add(New MailAddress("email#email.com"))
_with1.Subject = "Test Email"
_with1.Priority = priority
Dim htmlView As AlternateView = AlternateView.CreateAlternateViewFromString(bodyMessage(0), Nothing, "text/html")
Dim plainView As AlternateView = AlternateView.CreateAlternateViewFromString(bodyMessage(1), Nothing, "text/plain")
_with1.AlternateViews.Add(plainView)
_with1.AlternateViews.Add(htmlView)
SMTPClientConnection.Send(smtpMessage)
Return True
End Using
Else
Throw New SmtpException("Invalid email.")
End If
End If
Catch ex As Exception
End Try
Return functionReturnValue
End Function
I use the function on my code here:
Dim plainBody As String = File.ReadAllText(HttpContext.Current.Server.MapPath("email.txt"))
plainBody = plainBody.Replace("%Name%", emailName)
Dim emailBody As List(Of String) = New List(Of String)(New String() {plainBody})
SendEmail("email#email.com", emailBody, MailPriority.Normal)

Answer 1

The compiler error message is clear. The variable SmtpClientConnection is an instance variable (it exists as a different entity in any class instance where is declared) but you are trying to use inside a Shared method (a method that exists without a class instance). Inside this kind of methods you cannot use instance variables because you don't have an instance from which the method could pick the variable value and use it.
The solution could be to remove the Shared keyword from the method and then, whenever you want to call the method you need to create an instance of the class where the instance variable SmtpClientConnection is initialized and ready to be used in the following call to the SendMail method.
However, you could still use the Shared method but should remove the instance variable and create it inside the SmtpClient method:
Private Shared Function SendEmail(ByVal emailUser As String, ByVal bodyMessage As List(Of String), ByVal priority As MailPriority) As Boolean
Dim functionReturnValue As Boolean = False
Try
If Not String.IsNullOrWhiteSpace(emailUser) Then
If Regex.IsMatch(emailUser, "^([a-zA-Z0-9]+([\.+_-][a-zA-Z0-9]+)*)#(([a-zA-Z0-9]+((\.|[-]{1,2})[a-zA-Z0-9]+)*)\.[a-zA-Z]{2,6})$") Then
Dim SMTPClientConnection As SmtpClient = New SmtpClient
SMTPClientConnection.Host = "HOSTHERE"
SMTPClientConnection.Port = PORTHERE
SMTPClientConnection.DeliveryMethod = SmtpDeliveryMethod.Network
Using SMTPClientConnection
Dim smtpMessage As MailMessage = New MailMessage()
......
SMTPClientConnection.Send(smtpMessage)
Return True
End Using
Else
Throw New SmtpException("Invalid email.")
End If
End If
Catch ex As Exception
' No point in catching an exception and doing nothing here.
' You can log the exception somewhere and then throw it again
LogException(ex)
Throw
' or just remove the try/catch block.
End Try
Return functionReturnValue
End Function
In this way the variable is created only when needed and destroyed as well when the using statement ends. Take also note of the comments relative to the Try/Catch block.