SendMailErrorEventArgs.Exception Property
Returns the exception thrown by an SMTP mail service when an e-mail message cannot be sent.
Assembly: System.Web (in System.Web.dll)
The Exception property contains the exception that is thrown by the SMTP mail provider when an e-mail message cannot be sent by the ChangePassword control or the CreateUserWizard. The most common reason for this exception is a configuration error in the <smtp> Element (Network Settings) of the machine configuration file, which produces the following exception message: The transport failed to connect to the server.
Exceptions are not thrown if there is an error in the e-mail message when embedding a file using EmbeddedObjects. Instead, the embedded file appears broken when the mail message is viewed.
You must set the Handled object, passed as the e parameter of SendMailErrorEventArgs, to true to signal that the exception has been handled; otherwise, the exception is rethrown, and includes the original call stack and error message.
The following code example demonstrates an ASP.NET page that uses a ChangePassword Web control, and includes an event handler for the SendMailError event named SendMailError. The code example assumes that the ASP.NET Web site has been configured to use ASP.NET membership and Forms authentication, and that a user has been created whose name and password are known to you. For more information, see How to: Implement Simple Forms Authentication.
If the password change succeeds, the code in the SendingMail event handler attempts to send an e-mail message to the user to confirm the change. SMTP must already be configured on the server in order for this code example to work. For information about how to configure an SMTP server, see NIB: How to: Install and Configure SMTP Virtual Servers in IIS 6.0. For the purposes of this example, it is not necessary to configure an SMTP server; the example is constructed to test for a failure to send an e-mail message.
If a mail server is not configured correctly or some other error occurs and the e-mail message cannot be sent, the SendMailError function is called. A message is displayed to the user. In addition, an event is logged to the Windows Application event log with the assumption that an event source named MySamplesSite already exists. See the code example below to create the specified event source. For more information about creating an event source, see Server Event Handling in ASP.NET Web Forms Pages. The Handled property of the SendMailErrorEventArgs object is set to true to indicate that the error has been handled.
<%@ Page Language="VB" AutoEventWireup="True" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> Public Sub MySendingMail(ByVal Sender As Object, ByVal e As MailMessageEventArgs) Message1.Text = "Sent mail to you to confirm the password change." End Sub Public Sub MySendMailError(ByVal Sender As Object, ByVal e As SendMailErrorEventArgs) Message1.Text = "Could not send mail to confirm the password change." ' The MySamplesSite event source has already been created by an administrator. Dim myLog As System.Diagnostics.EventLog myLog = new System.Diagnostics.EventLog myLog.Log = "Application" myLog.Source = "MySamplesSite" myLog.WriteEntry("Sending mail via SMTP failed with the following error: " & e.Exception.Message.ToString(), System.Diagnostics.EventLogEntryType.Error) e.Handled = True End Sub </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>ChangePassword including a SendMailError Event</title> </head> <body> <form id="form1" runat="server"> <div style="text-align:center"> <h1>ChangePassword</h1> <asp:LoginView ID="LoginView1" Runat="server" Visible="true"> <LoggedInTemplate> <asp:LoginName ID="LoginName1" Runat="server" FormatString="You are logged in as {0}." /> <br /> </LoggedInTemplate> <AnonymousTemplate> You are not logged in </AnonymousTemplate> </asp:LoginView><br /> <asp:ChangePassword ID="ChangePassword1" Runat="server" BorderStyle="Solid" BorderWidth="1" CancelDestinationPageUrl="~/Default.aspx" DisplayUserName="true" OnSendingMail="MySendingMail" OnSendMailError="MySendMailError" ContinueDestinationPageUrl="~/Default.aspx" > <MailDefinition BodyFileName="~\MailFiles\ChangePasswordMail.htm" Subject="Activity information for you"> <EmbeddedObjects> <asp:EmbeddedMailObject Name="LoginGif" Path="~\MailFiles\Login.gif" /> <asp:EmbeddedMailObject Name="PrivacyNoticeTxt" Path="~\MailFiles\PrivacyNotice.txt" /> </EmbeddedObjects> </MailDefinition> </asp:ChangePassword><br /> <asp:Label ID="Message1" Runat="server" ForeColor="Red" /><br /> <asp:HyperLink ID="HyperLink1" Runat="server" NavigateUrl="~/Default.aspx"> Home </asp:HyperLink> </div> </form> </body> </html>
Use the following code example if you need to programmatically add the event source named MySamplesSite to your Application log. This event source must exist in order for the first code example to work correctly. The following code example requires Administrator privileges.
Imports System Imports System.Collections.Generic Imports System.Text Imports System.Diagnostics Namespace CreateEventSource Class Program Sub Main() Try ' Create the source, if it does not already exist. If Not (EventLog.SourceExists("MySamplesSite")) Then EventLog.CreateEventSource("MySamplesSite", "Application") Console.WriteLine("Creating Event Source") End If ' Create an EventLog instance and assign its source. Dim myLog As New EventLog myLog.Source = "MySamplesSite" ' Write an informational entry to the event log. myLog.WriteEntry("Testing writing to event log.") Console.WriteLine("Message written to event log.") Catch e As Exception Console.WriteLine("Exception:") Console.WriteLine(e.ToString) End Try End Sub End Class End Namespace
Available since 2.0