使用php循环多维数组以生成表列和行

Question

I have the following array which came up from my two days work with arrays.

Array (
      [0]=> Array(
            [6]=>Array(
                  [English] => 17
                  [Maths] => 11
                  [Science] => 15
                  )
              )
      [1] =>Array(
            [7]=>Array(
                  [English] => 13
                  [Maths] => 15
                  [Science] => 11
                  )
             )
      [2] =>Array(
            [8]=>Array(
                  [English] => 9
                  [Maths] => 17
                  [Science] => 9
                  )
             )
     )

Here array key 6,7, and 8 are unique. I want to print out this array in this format.

<table border="1">
  <thead>
    <tr>
      <th>Roll No</th>
      <th>English</th>
      <th>Maths</th>
      <th>Science</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>6</td>
      <td>17</td>
      <td>11</td>
      <td>15</td>
    </tr>
    <tr>
      <td>7</td>
      <td>13</td>
      <td>15</td>
      <td>11</td>
    </tr>
    <tr>
      <td>8</td>
      <td>9</td>
      <td>17</td>
      <td>9</td>
    </tr>
  </tbody>
  </table>

Note: the header and the rows are dynamic.

</div>

Answer 1

Given this array structure (taken from your question, put into code):

$rows = array(
    array(
        6 => array(
            'English' => 17,
            'Maths' => 11,
            'Science' => 15
        )
    ),
    array(
        7 => array(
            'English' => 13,
            'Maths' => 15,
            'Science' => 11
        )
    ),
    array(
        8 => array(
            'English' => 9,
            'Maths' => 17,
            'Science' => 9
        )
    )
);

First, get all the subjects (English, Maths, Science, etc) that need to be displayed:

$columns = array();

foreach ($rows as $row) {
    foreach ($row as $roll => $set) {
        foreach ($set as $class => $score) {
            $columns[$class] = $class;
        }
    }
}

Then, display them (quick and dirty):

<table border="1">
    <thead>
        <tr>
            <th>Roll No</th>
        <?php
            foreach ($columns as $column) {
                echo '<th>' . $column . '</th>';
            }
        ?>
        </tr>
    </thead>
    <tbody>
    <?php
        foreach ($rows as $row) {
            echo '<tr>';
            foreach ($row as $roll => $set) {
                echo '<td>' . $roll . '</td>';
                foreach ($columns as $class) {
                    echo '<td>' . ((array_key_exists($class, $set)) ? $set[$class] : 'n/a') . '</td>';
                }
            }
            echo '</tr>';
        }
    ?>
    </tbody>
</table>