Use a CustomControl to Set UserId and Use as a DataBindable Property

Use a CustomControl (named MembershipUser) to Set UserId and Use as a DataBindable Property. Create a MembershipUser CustomControl that has a property named Value that can be DataBound. For example MembershipUser1.Value would fetch the userId:

    [Browsable (true)]
    public string Value
    {
        get
        {
            MembershipUser currentUser;
            currentUser = Membership.GetUser();
            if (currentUser == null)
                return string.Empty;
            return currentUser.ProviderUserKey.ToString();
        }
    }

Reference: This is from http://aspnet.4guysfromrolla.com/articles/110106-1.aspx