PHP未定义索引[重复]

Question

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• “Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP 28 answers

I have this code and it's giving me an undefined error if country is not a variable in the URL. I've never had this problem before so it's obviously something to do with server settings but I'd rather not change those because this is probably done for security purposes. I've searched Google and can't find the workaround, although I'm sure it's blindingly obvious!

$country = $_GET['country'];

    if(!$country){
        $incoming = $outgoing = $sms = $free = "---";
    } else {
        get_rates($country);
    }

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Answer 1

you should use the following approach:

if (!isset($_GET['country'])) {
    $incoming = $outgoing = $sms = $free = "---";
} else {
    get_rates($_GET['country']);
}