是否可以在CustomAttribute中重新绑定IPrincipal？

public class CustomPrincipal : IPrincipal
{
    private IIdentity _identity;
    private string[] _roles;

    public CustomPrincipal(IIdentity identity, string[] roles)
    {
        _identity = identity;
        _roles = roles;
    }

    public IIdentity Identity
    {
        get { return _identity; }
    }

    public bool IsInRole(string role)
    {
        return _roles.Contains(role);
    }
}

// 在需要重新绑定的地方
var identity = new GenericIdentity("username");
var roles = new string[] { "role1", "role2" };
var principal = new CustomPrincipal(identity, roles);
HttpContext.Current.User = principal;