src/LightSaml/SamlConstants.php
public static function isNameIdFormatValid($value)
    {
        static $arr = array(
            self::NAME_ID_FORMAT_NONE,
            self::NAME_ID_FORMAT_ENTITY,
            self::NAME_ID_FORMAT_PERSISTENT,
            self::NAME_ID_FORMAT_TRANSIENT,
            self::NAME_ID_FORMAT_EMAIL,
            self::NAME_ID_FORMAT_SHIB_NAME_ID,
            self::NAME_ID_FORMAT_X509_SUBJECT_NAME,
            self::NAME_ID_FORMAT_WINDOWS,
            self::NAME_ID_FORMAT_KERBEROS,
            self::NAME_ID_FORMAT_UNSPECIFIED,
        );

        return in_array($value, $arr);
    }
public static function isNameIdFormatValid($value)
    {
        static $arr = array(
            self::NAME_ID_FORMAT_NONE,
            self::NAME_ID_FORMAT_ENTITY,
            self::NAME_ID_FORMAT_PERSISTENT,
            self::NAME_ID_FORMAT_TRANSIENT,
            self::NAME_ID_FORMAT_EMAIL,
            self::NAME_ID_FORMAT_SHIB_NAME_ID,
            self::NAME_ID_FORMAT_X509_SUBJECT_NAME,
            self::NAME_ID_FORMAT_WINDOWS,
            self::NAME_ID_FORMAT_KERBEROS,
            self::NAME_ID_FORMAT_UNSPECIFIED,
        );

        return in_array($value, $arr);
    }
@param string $value

@return bool