我想使用此 php 代码逐行获取数据，但它发生的错误是，即未定义的索引:我该怎么办 - I want to fetch data row by row by using this php code but its occurring error i,e Undefined index: what should i do?

I want to fetch data row by row by using this php code but its occurring error i,e Undefined index: what should i do?

<?php
$con = mysqli_connect("localhost","root","","test") or die('error');
$query = "select * from data" ;
$result = mysqli_query($con,$query);
while($row = mysqli_fetch_row($result)){
    $num_id = $row['id'];
    $arr_question = $row['question'];
    $a = $row['option_a'];
    $b = $row['option_b'];
    $c = $row['option_c'];
    $d = $row['option_d'];
    $answere = $row['answere'];
    $description = $row['description'];
}
?>

我想使用此代码从数据库中获取数据，但是当我使用 mysqli_fetch_array它返回表的最后一行，当我使用mysqli_fetch_row它返回未定义的索引。

现在请帮助我，对我来说应该采取什么正确的步骤？

您在while循环期间覆盖变量，因此在循环结束时，您的变量将包含最后一行的值。

尝试将每行的值存储到数组中，然后稍后处理数组，您可以使用关联数组，例如：

$results = array();
while($row = mysqli_fetch_row($result)){
    $results[] = array(
                 'num_id'=> $row['id'],
                 'arr_question' => $row['question'],
                 'a' => $row['option_a'],
                 'b' => $row['option_b'],
                 'c' => $row['option_c'],
                 'd' = $row['option_d'],
                 'answer' => $row['answere'],
                 'description' => $row['description']
             );
}
print_r($results);