如何在mysqlphp中更新多选下拉数组 - How to update multiselect dropdown array in mysql php

我在项目中使用多选下拉菜单。现在我想更新mysql数据库中的multiselect下拉数组值。我成功地在数据库中添加了多选值，但当我试图更新时，我得到了错误的结果。例如，如果数组中的值像这样array（[0]=>A[1]=>B），并且我运行一个循环来更新DB中的值，那么更新的值总是数组的第二个值（例如[1]=>B（））。我不知道问题出在哪里请帮忙。。下面是我的代码。。

HTML

<select name="countries[]" id="countries" multiple="multiple" placeholder="Which countries did you sell your products in *" required>
<option value="" disabled="disabled" selected>Which countries did you sell your products in *</option>
<option value="Afghanistan">Afghanistan</option>
<option value="Albania">Albania</option>
<option value="Algeria">Algeria</option>
<option value="American Samoa">American Samoa</option>
<option value="Andorra">Andorra</option>
<option value="Angola">Angola</option>
<option value="Anguilla">Anguilla</option>

PHP

$countries = $_POST['countries'];
$user_id = $_SESSION['user_session'];
$size=sizeof($countries);
for($i=0;$i<$size;){
    $count = $trade_info->update_supplier_last_financial_count($user_id, $countries[$i]);
    $i++;
}

功能（update_supplier_last_financial）

public function update_supplier_last_financial_count($user_id,$last_count){
    $db = db::getInstance();    
    $pdo = $db->getConnection();
    try {
        $stmt = $pdo->prepare("UPDATE supplier_last_financial_countries SET countries = :last_count WHERE user_id = :user_id ");
        $stmt->bindparam(":user_id", $user_id);
        $stmt->bindparam(":last_count", $last_count);
        $stmt->execute();
        return $stmt;   
    }
    catch(PDOException $e) {
        echo $e->getMessage();
    }
}

提前谢谢。。

您的查询正在一次又一次地更新同一一路领先。它受到WHERE的限制，但WHERE（$user_id）的条件从未改变。

像这样的东西可能会起作用：

$countries = $_POST['countries'];
$user_id = $_SESSION['user_session'];
foreach ($countries as $country) {
    $count = $trade_info->update_supplier_last_financial_count($user_id, $country);
}
public function update_supplier_last_financial_count($user_id,$last_count) {
    $db = db::getInstance();    
    $pdo = $db->getConnection();
    try {
        $stmt = $pdo->prepare("DELETE FROM supplier_last_financial_countries WHERE user_id = :user_id ");
        $stmt->bindparam(":user_id", $user_id);
        $stmt->execute();
        $stmt = $pdo->prepare("INSERT INTO supplier_last_financial_countries SET countries = :last_count, user_id = :user_id ");
        $stmt->bindparam(":user_id", $user_id);
        $stmt->bindparam(":last_count", $last_count);
        $stmt->execute();
        return $stmt;   
    } catch(PDOException $e) {
        echo $e->getMessage();
    }
}

如果需要在一列中存储多个国家/地区，则应将它们存储为一个集合（即字符串中逗号分隔的值）。试试这个。

  $countries = $_POST['countries'];
  $user_id = $_SESSION['user_session'];
  $countriesValues = implode(',', $countries);//store country values as a set
  $count = $trade_info->update_supplier_last_financial_count($user_id, $countriesValues);

为此，您需要将数据类型从int更改为varchar您也可以以相同的方式更新国家/地区值。