如何从key返回PHP数组值?

dmu*_*ubu 3 php arrays loops

我正在尝试根据选择菜单中的城市选择生成用户的国家/地区.我使用关联数组生成了选择菜单.我想打印"$ city in $ country"但我无法正常访问$ country.这就是我所拥有的:

<?php
$cities = array("Tokyo" => "Japan", "Mexico City" => "Mexico", 
"New York City" => "USA", "Mumbai" => "India", "Seoul" => "Korea",
"Shanghai" => "China", "Lagos" => "Nigeria", "Buenos Aires" => "Argentina", 
"Cairo" => "Egypt", "London" => "England");
?>

<form method="post" action="5.php">
<?php
echo '<select name="city">';

foreach ($cities as $city => $country)
{
echo '<option value="' . $city . '">' . $city . '</option>';
}

echo '<select>';

?>

<input type="submit" name="submit" value="go" />
</form>
<?php
$city = $_POST["city"];

print ("$city is in $country");
?>
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有任何想法吗?谢谢.

Spy*_*ros 9

您正试图从foreach循环中访问本地foreach变量$ country.你必须在循环中做到这一点.

或者你可以从城市阵列获得这样的国家:

$cities[$city];
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