找到在php循环中生成的变量

Question

I have this php code:

for($i=0;$i<3;$i++) {
    echo 'Question'.$i.'</br>';
    echo 'Answer..</br>';
    echo '<form action="" method="POST">';
    echo '<textarea name="answer"></textarea>';
    echo '</br><button name="answer_button'.$i.'"><b>Answer</b></button>';
    echo '</form>';
}

Now I want to get the question number for which the answer_button is clicked.

Closest I could get was this:

for($i=0;$i<3;$i++) {   
    echo 'Question'.$i.'</br>';
    echo 'Answer..</br>';
    echo '<form action="" method="POST">';
    echo '<textarea name="answer"></textarea>';
    echo '</br><button name="answer_button"><b>Answer</b></button>';
    echo '</form>';
    if(isset($_POST['answer_button'])) {
         echo $i;
         break;
     }
}

This gives me Question number but it will not print other questions in loop once the button is clicked.

Is there no solution without using javaScript?

Answer 1

Change the html markup to use an "array notation":

echo '<button name="answer_button['.$i.']" type="submit">Answer</button>';

That will cause php to populate an array when receiving back the form which you can examine:

<?php
// ...
if(isset($_POST['answer_button']) && is_array($_POST['answer_button'])) {
    $id = array_shift(array_keys($_POST['answer_button']));
    // ...
}

This allows to have multiple such buttons in a single form and detect which one has actually been clicked. It works, because $_POST will contain an array with a single element with key as in $id, which you can easily examine yourself with a var_dump($_POST); or similar.