php - 如何在 PHP 中通过 while 循环检索数据

Question

我正在循环查看 MySQL 结果，但遇到了问题。问题是只有我的第一个 if 语句正在执行。我的其余 if 语句返回空字符串。让我困惑的是:当我删除 while 循环中的第一个 if 语句时，下一个 if 语句将返回数据，但其下面的所有其他语句都不会。

这是我的相关代码:

// Get Addresses
$queryAddresses  = "SELECT * FROM contact_addresses WHERE contact_id = $contactID";
$resultAddresses = mysqli_query($dbc, $queryAddresses);
$numAddresses    = mysqli_num_rows($resultAddresses);

if ($numAddresses >= 1) {
    $address_labels = '';
    $addresses      = '';
    while ($address = mysqli_fetch_array($resultAddresses, MYSQLI_ASSOC)) {
        $address_labels .= $address['label'].'<br>';

        if (!empty($address['address'])) {
            $address = $address['address'].', ';
        } else {
            $address = '';
        }
        
        /* ALL OF THE IF STATEMENTS BELOW THIS LINE RETURN EMPTY STRINGS EVEN THOUGH THE INFORMATION IS STORED IN THE DATABASE.  */
        if (!empty($address['address_two'])) {
            $address_two = $address['address_two'].', ';
        } else {
            $address_two = '';
        }

        if (!empty($address['city'])) {
            $city = $address['city'].', ';
        } else {
            $city = '';
        }

        if (!empty($address['state'])) {
            $state = $address['state'].', ';
        } else {
            $state = '';
        }

        if (!empty($address['zip'])) {
            $zip = $address['zip'].', ';
        } else {
            $zip = '';
        }

        if (!empty($address['country'])) {
            $country = $address['country'].', ';
        } else {
            $country = '';
        }

        $addresses .= $address.''.$address_two.''.$city.''.$state.''.$zip.''.$country.'<br>';
    }
}

Answer 1

使用 $address = $address['address'].', '; 行，您将用新字符串替换 $address 数组并清除大批。尝试更改字符串变量名称:

    if (!empty($address['address'])) {
        $address_one = $address['address'].', ';
    } else {
        $address_one = '';
    }

    if (!empty($address['address_two'])) {
        $address_two = $address['address_two'].', ';
    } else {
        $address_two = '';
    }

    if (!empty($address['city'])) {
        $city = $address['city'].', ';
    } else {
        $city = '';
    }

    if (!empty($address['state'])) {
        $state = $address['state'].', ';
    } else {
        $state = '';
    }

    if (!empty($address['zip'])) {
        $zip = $address['zip'].', ';
    } else {
        $zip = '';
    }

    if (!empty($address['country'])) {
        $country = $address['country'].', ';
    } else {
        $country = '';
    }

    $addresses .= $address_one.''.$address_two.''.$city.''.$state.''.$zip.''.$country.'<br>';