To make a theme "stick" with a user, you'll need a profile property to store his or her favorite theme name. Going back to our first web.config example in Listing 12.1, you simply need to add a profile property called Theme and set its type to System.String. Regardless of the profile provider you use (unless of course your own custom provider doesn't deal with the Theme property), Listing 12.11 shows how your page can set the theme for the user.
C#
void Page_PreInit(object sender, EventArgs e)
{
Theme = Profile.Theme;
}
VB.NET
Sub Page_PreInit(sender As Object, e As EventArgs) Theme = Profile.Theme End Sub