如何處理記帳系統中的貨幣轉換功能 - 使用PHP實現貨幣轉換的開發方法

// 使用curl获取实时汇率数据
$curl = curl_init();
curl_setopt_array($curl, array(
    CURLOPT_URL => "https://api.exchangerate-api.com/v4/latest/USD", // 这里以美元为基准获取其他货币的汇率
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_ENCODING => "",
    CURLOPT_MAXREDIRS => 10,
    CURLOPT_TIMEOUT => 30,
    CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
    CURLOPT_CUSTOMREQUEST => "GET",
    CURLOPT_HTTPHEADER => array(
        "cache-control: no-cache"
    ),
));
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);

if ($err) {
    echo "cURL Error #:" . $err;
} else {
    $currencyData = json_decode($response, true);
    $exchangeRates = $currencyData['rates'];
}

function convertCurrency($amount, $from, $to, $exchangeRates) {
    if ($from == $to) {
        return $amount;
    }

    // 使用汇率进行货币转换
    $convertedAmount = $amount / $exchangeRates[$from] * $exchangeRates[$to];
    
    return $convertedAmount;
}

$amount = 100; // 转换前的金额
$from = 'USD'; // 转换前的货币
$to = 'EUR'; // 转换后的货币

$convertedAmount = convertCurrency($amount, $from, $to, $exchangeRates);

echo $amount . ' ' . $from . ' = ' . $convertedAmount . ' ' . $to;