public override bool RoleExists(string roleName)
{
if (Utils.StringIsNullOrWhitespace(roleName))
{
throw new ArgumentNullException("roleName");
}
else
{
// Role names are not supposed to be case sensitive. This needs to be kept consistent with
// other RoleProvider classes.
return (this.GetAllRoles().Contains(roleName, StringComparer.OrdinalIgnoreCase));
}
}