PHP擷取目前頁面完整URL位址

/**

 * 擷取目前頁面完整URL位址

 */

function get_url() {

    $sys_protocal = isset($_SERVER['SERVER_PORT']) && $_SERVER['SERVER_PORT'] == '443' ? 'https://' : 'http://';

    $php_self = $_SERVER['PHP_SELF'] ? $_SERVER['PHP_SELF'] : $_SERVER['SCRIPT_NAME'];

    $path_info = isset($_SERVER['PATH_INFO']) ? $_SERVER['PATH_INFO'] : '';

    $relate_url = isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : $php_self . (isset($_SERVER['QUERY_STRING']) ? $_SERVER['QUERY_STRING'] : $path_info);

    $relate_url = $sys_protocal . (isset($_SERVER['HTTP_HOST']) ? $_SERVER['HTTP_HOST'] : '') . $relate_url;

    return urlencode($relate_url);

}