The below code is ok to update the Email in the membership

    MembershipUser currentUser = Membership.GetUser();
    currentUser.Email = NewEmail.Text;
    Membership.UpdateUser(currentUser);

I'd like to change the UserName of membership

    MembershipUser currentUser = Membership.GetUser();
    currentUser.UserName = NewUserName.Text;
    Membership.UpdateUser(currentUser);

There are some errors:
    "currentUser.UserName" is readOnly

How can I do?

username is a readonly field so you actually cannot change it.
however, I found this via google and it seems a nice solution to me (havent tested it)

http://msmvps.com/blogs/omar/archive...18/108003.aspx

thanks vantoko
Yes, I'v changed the username, but there are something leave in the user and profile tables.