此代碼將貨幣切換器添加到菜單中，但不幸的是我無法訪問 MySQL 數(shù)據(jù)庫，所以我無法為每種貨幣添加圖像“標(biāo)志”，然后執(zhí)行它們所以我嘗試使用if語句。這是我的代碼：$currency_switcher_enable = houzez_option('currency_switcher_enable');$is_multi_currency = houzez_option('multi_currency');if( $currency_switcher_enable != 0 && $is_multi_currency != 1 ) {    if (class_exists('FCC_Rates')) {        $supported_currencies = houzez_get_list_of_supported_currencies();        if (0 < count($supported_currencies)) {            $current_currency = houzez_get_wpc_current_currency();            echo '<li class="btn-price-lang btn-price">';                        echo '<form id="houzez-currency-switcher-form" method="post" action="#" class="open">';            echo '<button id="houzez-selected-currency" class="btn dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true"><span>' . $current_currency . '</span> <i class="fa fa-sort"></i></button>';            echo '<ul id="houzez-currency-switcher-list" class="dropdown-menu" aria-labelledby="dropdown" style="display:none;">';            foreach ($supported_currencies as $currency_code) {                echo '<li data-currency-code="' . $currency_code . '">' . $currency_code . '</li>';                if (data-currency-code='EUR') {                    echo '<img src="images/euro-flag.png"';                    if (data-currency-code='TR') {                    echo '<img src="images/turkish-flag.png"';                }            }            echo '</ul>';            echo '<input type="hidden" id="houzez-switch-to-currency" name="houzez_switch_to_currency" value="' . $current_currency . '" />';            echo '<input type="hidden" id="currency_switch_security" name="nonce" value="' . wp_create_nonce('houzez_currency_converter_nonce') . '"/>';            echo '</form>';            echo '</li>';        }    }}?>但這不起作用？我做錯(cuò)了什么？