Arash.Membership.Site.MemberService.ChangePassword C# (CSharp) Method

        public bool ChangePassword(string username, string oldPassword, string newPassword)
        {
            if (String.IsNullOrEmpty(username) || String.IsNullOrEmpty(oldPassword) || String.IsNullOrEmpty(newPassword))
                return false;

            var currentUser = _memberManager.Get(p => p.Username == username);

            if (currentUser != null)
                return false;

            if (!PasswordGenerator.Equals(oldPassword, currentUser.Password))
            {
                return false;
            }

            currentUser.Password = PasswordGenerator.GetHashPassword(newPassword);

            _memberManager.Edit(currentUser);
            return true;
        }