Php - 变量名中的变量

Question

我有一个带有多个复选框的表单。如果选中，这些框在 mysql 数据库中各占一行。现在，我需要一个循环来构建查询以删除所有未选中的行。我尝试了下面的一个，但数组从未填充过......感谢任何帮助...

$chk_cab_1  = isset($_POST['chk_cab_1']) ?: 0;
$chk_cab_2  = isset($_POST['chk_cab_2']) ?: 0;
$chk_cab_3  = isset($_POST['chk_cab_3']) ?: 0;
$chk_cab_4  = isset($_POST['chk_cab_4']) ?: 0;
$chk_cab_5  = isset($_POST['chk_cab_5']) ?: 0;
$chk_cab_6  = isset($_POST['chk_cab_6']) ?: 0;
$chk_cab_7  = isset($_POST['chk_cab_7']) ?: 0;
$chk_cab_8  = isset($_POST['chk_cab_8']) ?: 0;
$chk_cab_9  = isset($_POST['chk_cab_9']) ?: 0;
$chk_cab_10 = isset($_POST['chk_cab_10']) ?: 0;
$chk_cab_11 = isset($_POST['chk_cab_11']) ?: 0;


$check_cab    = array();
$del_cab_ids  = array();
for($i = 1; $i<=$counter; $i++) {
    $check_cab["chk_cab_$i"]     = $chk_cab_$i;
    if($check_cab["chk_cab_$i"] == 0) {
       $del_cab_ids[] = $i;
    }
}

$sql = "DELETE FROM mytable 
        WHERE first_id = $t_key
        AND second_id IN ($del_cab_ids)";

Answer 1

我会更改 HTML，如果可能的话，像这样重命名复选框:

<input name="chk_cab[0]" type="checkbox" value="1" />
...
<input name="chk_cab[5]" type="checkbox" value="1" />
...

然后反转查询:

$sql = "DELETE FROM mytable WHERE first_id = ?";

if (isset($_POST['chk_cab']) {
    $ids = join(',', array_map('intval', array_keys($_POST['chk_cab'])));

    $sql .= " AND second_id NOT IN ($ids)";
}

重要:这假设所有条目都匹配 first_id = <whatever>占 [1 .. $counter] 内.