Php xml到mysql simplexml\u加载\u字符串，无插入

不会插入值，也不会显示错误。你知道我的插页是怎么回事吗

<?php
$string = <<<XML
<?xml version='1.0'?> 
<setnames>
<country>
<countryCode>AD</countryCode>
<countryName>Andorra</countryName>
</country>
<country>
<countryCode>AE</countryCode>
<countryName>United Arab Emirates</countryName>
<isoNumeric>784</isoNumeric>
</country>
<country>
<countryCode>AF</countryCode>
<countryName>Afghanistan</countryName>
<isoNumeric>784</isoNumeric>
</country>
</setnames>
XML;

$xml = simplexml_load_string($string);

foreach ($xml as $country) 
{

mysqli INSERT INTO setnames 
VALUES ($country->countryCode, $country->countryName, $country->isoNumeric);

    echo $country->countryCode . "<br />";
    echo $country->countryName . "<br />";
    echo $country->isoNumeric . "<br />"
}

countryCode，$country->countryName，$country->isoNumeric）；
echo$country->countryCode。“
”；
echo$country->countryName。“
”；
echo$country->isoNumeric。“
”
}

$xml变量既不是对象，也不是数组。所以，你应该这样做：

foreach ($xml->country as $country) 
{

mysqli INSERT INTO setnames 
VALUES ($country->countryCode, $country->countryName, $country->isoNumeric);

    echo $country->countryCode . "<br />";
    echo $country->countryName . "<br />";
    echo $country->isoNumeric . "<br />"
}

foreach（$xml->country as$country）
{
mysqli插入到setnames中
值（$country->countryCode、$country->countryName、$country->isoNumeric）；
echo$country->countryCode.“
”；
echo$country->countryName.“
”；
echo$country->isoNumeric。“
”
}

什么显示了变量转储（$xml）？