A System.Web.Security.MembershipUserCollection of System.Web.Security.MembershipUser objects representing all of the users in the database.
Membership.GetAllUsers returns the information for all membership users for an application as a collection of System.Web.Security.MembershipUser objects. Be careful when using the Membership.GetAllUsers method with very large user databases, as the resulting System.Web.Security.MembershipUserCollection in your ASP.NET page may degrade the performance of your application.