ChangePassword.SendMailError Event

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Occurs when there is an SMTP error sending an email message to the user.

public:
 event System::Web::UI::WebControls::SendMailErrorEventHandler ^ SendMailError;

public event System.Web.UI.WebControls.SendMailErrorEventHandler SendMailError;

member this.SendMailError : System.Web.UI.WebControls.SendMailErrorEventHandler

Public Custom Event SendMailError As SendMailErrorEventHandler

Event Type

SendMailErrorEventHandler

Examples

The following code example demonstrates an ASP.NET page that uses a ChangePassword Web control, and includes an event handler for the SendingMail event named SendingMail. 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 attempts to use SMTP to send an email message to the user to confirm the change. This is done in theSendingMail event handler. For information about how to configure an SMTP server, see 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 email message.

If a mail server is not configured correctly or some other error occurs and the email 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="C#" 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">

  void MySendingMail(object sender, MailMessageEventArgs e)
  {
    Message1.Text = "Sent mail to you to confirm the password change.";
  }

  void MySendMailError(object sender, SendMailErrorEventArgs e)
  {
    Message1.Text = "Could not send email to confirm password change.";

    // The MySamplesSite event source has already been created by an administrator.
    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;
  }

</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>

<%@ 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.

#region Using directives

using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;

#endregion

namespace CreateEventSource
{
    class Program
    {
        static void Main(string[] args)
        {

            try
            {
                // Create the source, if it does not already exist.
                if (!EventLog.SourceExists("MySamplesSite"))
                {
                    EventLog.CreateEventSource("MySamplesSite", "Application");
                    Console.WriteLine("Creating Event Source");
                }

                // Create an EventLog instance and assign its source.
                EventLog myLog = 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 (Exception e)
            {
                Console.WriteLine("Exception:");
                Console.WriteLine("{0}", e.ToString());
            }
        }
    }
}

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

The following example code can be used as the ChangePasswordMail.htm file for the previous example code.

Important

Sending user account names or passwords in email is a potential security threat. Email messages are typically sent in plain text and can be read by special network "sniffing" applications. To improve security, use the mitigations that are described in Securing Login Controls.

<html>  
<head><title></title></head>  
<body>  
<form>  

  <h1>Your password for the account named &quot;<%Username%>&quot; has changed.</h1>  

  <p>  
  If you did not initiate this change, please call 1-206-555-0100.  
  </p>  

  <p>  
  <a href="http://www.contoso.com/login.aspx">  
    <img src="cid:LoginGif" alt="Log In" />  
  </a>   
  </p>  

  <p>  
  Please read our attached Privacy Notice.  
  </p>  

</form>  
</body>  
</html>

Remarks

The SendMailError event is raised when the SMTP mail provider throws an exception when trying to send an email message after users have changed their password. The most common reason that this event is raised is that the smtp section of the Web.config file is incorrect. For more information about the smtp section, see <smtp> Element (Network Settings).

The default SendMailError event handler does not catch or handle the SMTP error from the mail system. Your SendMailError event handler must set the Handled property of the SendMailErrorEventArgs object to true in order to stop the error from being displayed to users.

For more information about handling events, see Handling and Raising Events.

Applies to

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