dou-smallapp/app/Support/helpers.php

<?php
if (!function_exists('getInfoFromXml')) {
    /**
     * 读取xml字符串，获取对应数据
     * @return string
     */
    function getInfoFromXml($xmlStr, $field)
    {
        $xml_tree = new \DOMDocument();
        $xml_tree->loadXML($xmlStr);
        $array_e = $xml_tree->getElementsByTagName($field);
        $info = $array_e->item(0)->nodeValue;
        return $info;
    }
}