Occurs before the user name is validated by the membership provider.
Assembly: System.Web (in System.Web.dll)
The event is raised on the server before the user name is submitted to the membership provider to determine whether the user name is valid. Use this event to perform any preprocessing needed on the user name, such as converting it to all uppercase or lowercase letters, or verifying that the user name is in a particular format, such as an e-mail address.
The PasswordRecovery control first raises the event, and then uses the membership provider specified in the MembershipProvider property to determine whether the user name entered is a valid user name for the Web site. If it is valid, and the membership provider supports password question and answer, the password verification question is returned from the Web site and the PasswordRecovery control displays the Question view. If the user name is not valid, the text in the GeneralFailureText property is displayed in the UserName view so that the user can enter a different user name.
If the membership provider does not support password question and answer, the SendingMail event is raised and e-mail is sent to the user with the new or recovered password.
For more information about handling events, see Events and Delegates.
The following code example uses the event to check whether the submitted user name is formatted as a valid e-mail address. If the user name is not formatted properly, the UserNameInstructionText property is changed to show the error.