Php 将组合框中的选定值存储到数据库中

我试图创建一个带有文本输入和组合框的表单，其中包含从数据库检索到的值和数据。其思想是，当您提交表单时，文本字段中的值将存储在数据库的一个字段中。我需要做的是将组合框（而不是组合框中显示的文本）的选定值（数字值和从db的其他表中提取的值）存储到将存储表单文本字段的同一个表中

数据库结构由两个名为countries和addressions的表组成。国家/地区有一个名为country_id的字段和另一个名为country_name的字段（这两个字段填充组合框。表格名称有三个名为Attachion_id的字段（pk、nn、ai）、国家/地区id和称谓名称。称谓名称字段必须填写表单文本字段中提交的数据，国家/地区id必须填写组合框的选定值，该值等于国家/地区表的国家/地区id值。 到目前为止，我已经能够创建表单，并用db值加载combobox中的所有国家/地区

表格代码为

<form name="New Appellation" action="actions/register_appellation.php" method="POST"     onsubmit="return validate()">
Nombre denominacion de origen:
<input type="text" placeholder="Nombre DO" name="fappellation_name">
<br>
Pais denominacion de origen:
<?php
include_once 'includes/fast_conn.php';
mysqli_select_db($cn,$db_name) or die(mysql_error());
$sql = "SELECT country_name, country_id FROM countries";
$rs = mysqli_query($cn,$sql) or die(mysql_error());
echo "<select name='appellation_country'>";
while($row = mysqli_fetch_array($rs)){
echo "<option value='".$row["country_id"]."'>".$row["country_name"]."</option>";
}mysqli_free_result($rs);
echo "</select>";
?>
<input type="submit" value="Registrar">

</form>

原厂名称：


原发性血液透析：
我已经在下面列出了应该处理这个问题的修改后的来源

我在源代码中做了一些事情。我相信所有这些都应该被很好地记录下来。下面是我添加的事情列表：

代码现在已更新为完全使用MySQLi
两种形式的MySQLi都是OOP风格的（我更喜欢MySQLi）
有错误检查，看看事情是否成功，并相应地显示错误
register\u addression.php
现在检查字段是否已填写
register\u atternation.php
现在对查询变量执行卫生处理。（有助于防止SQL注入攻击）
register\u atternation.php
现在通过与
countries
表交叉引用来确认它收到的国家id是有效的

以下是表格代码：

<form name="New Appellation" action="actions/register_appellation.php" method="POST"    onsubmit="return validate()">
Nombre denominacion de origen:
<input type="text" placeholder="Nombre DO" name="fappellation_name">
<br>
Pais denominacion de origen:
<?php
include_once 'includes/fast_conn.php';
$boolSelectionSuccessful = $cn->select_db($db_name);
if(!$boolSelectionSuccessful){
    $deathMessage = "<br><div>" .
        "Oh no! An error occurred on our end!<br>" .
        "Here's what we know:<hr>" .
        $cn->error .
        "<hr>" .
        "If this error continues to occur, please contact the website administrator." .
        "</div>";
    die($deathMessage);
}
$sql = "SELECT `country_name`, `country_id` FROM `countries`";
$rs = $cn->query($sql);
if($rs === FALSE){
    $deathMessage = "<br><div>" .
        "Oh no! An error occurred on our end!<br>" .
        "Here's what we know:<hr>" .
        $cn->error .
        "<hr>" .
        "If this error continues to occur, please contact the website administrator." .
        "</div>";
    die($deathMessage);
}
echo "<select name='appellation_country'>";
while($row = $rs->fetch_assoc()){
    echo "<option value='".$row["country_id"]."'>".$row["country_name"]."</option>";
}
$rs->close();
echo "</select>";
?>
<input type="submit" value="Registrar">
</form>


原厂名称：


原发性血液透析：
您正在将MySQL API与
MySQL\u error（）
混合使用，它们不会混合使用。使用错误报告会发出这样的信号。将MySQL\u error（）更改为mysqli\u error（$cn），但没有更改。仍然得到通知：未定义索引：register_addression.php第4行中的country_id这是因为您的表单没有名为
country_id
的命名元素来处理
$fccountry_id=$\u POST['country_id']；
。其中唯一的元素是
，这就是为什么会出现未定义索引警告。另一件事是
$save=“插入$db\u name（$fccountry\u id，$$fappellation\u name）”
有两个
$
符号表示
$$fappellation\u name
另外，您不包括
值和列。即：
$save=“插入$db\u name（column1，column2）值（$fccountry\u id，$fappellation\u name）”
Fred，你能详细说明一下如何在html的combobox元素中命名一个名为country_id的元素吗？非常感谢你，我真的被困在这里了。谢谢你，Spencer，工作完美无瑕。insert mysql语句中缺少了几个单引号。工作完美再次感谢你！！哦，对不起，我会把它们添加进来的。无论如何，没问题。我还建议您在第一次打开连接时添加一个检查。这可以通过以下方式完成：
如果（$cn->connect\u error）{die（$cn->connect\u errno.
。$cn->connect\u error）；/*或任何其他您希望死亡的消息。*/}刚刚更新了MySQL语句中的错误，并将未定义的SturnID ID从“代码>未知国家代码”更改为“<代码> > <代码>未知国家。< /代码>，请考虑接受该答案，如果您满意，请将其进行投票。如果答案不被接受，它将作为未回答的问题而打开。
<form name="New Appellation" action="actions/register_appellation.php" method="POST"    onsubmit="return validate()">
Nombre denominacion de origen:
<input type="text" placeholder="Nombre DO" name="fappellation_name">
<br>
Pais denominacion de origen:
<?php
include_once 'includes/fast_conn.php';
$boolSelectionSuccessful = $cn->select_db($db_name);
if(!$boolSelectionSuccessful){
    $deathMessage = "<br><div>" .
        "Oh no! An error occurred on our end!<br>" .
        "Here's what we know:<hr>" .
        $cn->error .
        "<hr>" .
        "If this error continues to occur, please contact the website administrator." .
        "</div>";
    die($deathMessage);
}
$sql = "SELECT `country_name`, `country_id` FROM `countries`";
$rs = $cn->query($sql);
if($rs === FALSE){
    $deathMessage = "<br><div>" .
        "Oh no! An error occurred on our end!<br>" .
        "Here's what we know:<hr>" .
        $cn->error .
        "<hr>" .
        "If this error continues to occur, please contact the website administrator." .
        "</div>";
    die($deathMessage);
}
echo "<select name='appellation_country'>";
while($row = $rs->fetch_assoc()){
    echo "<option value='".$row["country_id"]."'>".$row["country_name"]."</option>";
}
$rs->close();
echo "</select>";
?>
<input type="submit" value="Registrar">
</form>

<?php
include_once '../includes/fast_conn.php';

function checkField($fieldName){
    if(isset($_POST[$fieldName])){
        if(!empty($_POST[$fieldName])){
            /* The request has the fieldName submitted && the fieldName was not left empty */
            return true;
        }else{
            return false;
        }
    }else{
        return false;
    }
}

$checkArray = array(checkField('fappellation_name'), checkField('appellation_country'));
if(in_array(false, $checkArray) || !is_numeric($_POST['appellation_country'])){
    /* the check assumes that 'appellation_country' (country id) should be numeric */
    die("<font size='+1' color='red'>Registration Failed. Please fill in all forms.</font>");
}

$boolSelectionSuccessful = $cn->select_db($db_name);
if(!$boolSelectionSuccessful){
    $deathMessage = "<br><div>" .
        "Oh no! An error occurred on our end!<br>" .
        "Here's what we know:<hr>" .
        $cn->error .
        "<hr>" .
        "If this error continues to occur, please contact the website administrator." .
        "</div>";
    die($deathMessage);
}
$sql = "SELECT `country_name`, `country_id` FROM `countries`";
$rs = $cn->query($sql);
if($rs === FALSE){
    $deathMessage = "<br><div>" .
        "Oh no! An error occurred on our end!<br>" .
        "Here's what we know:<hr>" .
        $cn->error .
        "<hr>" .
        "If this error continues to occur, please contact the website administrator." .
        "</div>";
    die($deathMessage);
}

$countryIdValid = False;
$countryName = "";
/* $countryName is unused, by the current code, but it will still be set in the while loop.
   If you want to store the country name in the `appeallations` table, this variable
   could simply be added to the insert statement. */

while($row = $rs->fetch_assoc()){
    if($row['country_id'] == $_POST['appellation_country']){
        $countryIdValid = true;
        $countryName = $row['country_name'];
        break;
    }
    /* else - continue looping to check the next country_id */
}

$rs->close();

/* now that the loop has been exited, we'll make sure the country_id was verified */
if(!$countryIdValid){
    die("<font size='+1' color='red'>Registration Failed. Unknown country.</font>");
}

$fappellation_name= $cn->real_escape_string($_POST['fappellation_name']);
$fcountry_id = $cn->real_escape_string($_POST['appellation_country']);
$save="INSERT INTO `appellations` (`country_id`, `appellation_name`) VALUES ('$fcountry_id', '$fappellation_name')";
$result = $cn->query($save);
if($result !== FALSE){
    echo "<font size='+1' color='blue'> " . $_POST['fappellation_name'] . ", Successfully Registered.</font>";
}else{
    $deathMessage = "<br><div>" .
        "Oh no! An error occurred on our end!<br>" .
        "Here's what we know:<hr>" .
        $cn->error .
        "<hr>" .
        "If this error continues to occur, please contact the website administrator." .
        "</div>";
    die($deathMessage);
}
?>