php - 每个循环错误的 PHP

Question

我有一个循环来遍历一个数组，每个checkbox被选中的我想将值（也动态引入）放入我的QuestionSelected表中。我收到此错误"Warning: Invalid argument supplied for foreach()"，无法将结果放入我的表中。这是我正在尝试的代码：

//Declare the QuestionID as a array
$QuestionID = array();


while($row = mysqli_fetch_array($run,MYSQLI_ASSOC)){
echo '<div id="QuestionSelection"><input id="chkQuestion" type="checkbox" value=" '.$row['QuestionID'].'" name="question_'.$row['QuestionID'].'">' .$row['Question']. '</p></div><br/><br/>';

//Assign the QuestionID from the table to the var
$QuestionID[] = $row['QuestionID'];

}


if($_POST['submitted']) { 


$ids_list = '';

foreach($_POST["QuestionID"] as $id)
{
$ids_list .= (strlen($ids_list) > 0 ? ',' : '').mysql_real_escape_string($id);
}

$sql2 = "INSERT INTO tbl_QuestionSelected (`QuestionID`) VALUES (".$ids_list.")";

}//End of IF 'submitted

Answer 1

The problem is that in your form, you are not using an array, but building the name values like:

name="question_'.$row['QuestionID'].'"

So $_POST["QuestionID"] does not exist and is not an array.

You can change your name building to:

name="QuestionID[]"

So that it is an array and you can even use the actual id as a key:

name="QuestionID[' . $row['QuestionID'] . ']"

Answer 2

这解决了问题并且有效：

$ids_list = '';

foreach($_POST["QuestionID"] as $key=>$value) {
{
$ids_list .= (strlen($ids_list) > 0 ? ',' : '').mysql_real_escape_string($value);
}

$sql2 = "INSERT INTO tbl_QuestionSelected (`QuestionID`) VALUES (".$ids_list.")";

//Run the query 
$run2 = @mysqli_query ($conn,$sql2);


}