Roles.RemoveUserFromRoles Method (String, String)
Removes the specified user from the specified roles.
Assembly: System.Web (in System.Web.dll)
One of the roles in roleNames is null.
username is null.
One of the roles in roleNames is an empty string or contains a comma (,).
username is an empty string or contains a comma (,).
roleNames contains a duplicate element.
Role management is not enabled.
Themethod calls the default role provider to remove the specified user from the specified roles at the data source.
If the application is configured to use the SqlRoleProvider class, the database updates that are performed during the call to the method are made within a transaction. If an error is encountered, such as a user name that is not in a specified role, the transaction is rolled back and no updates are performed.
Available since 2.0