php foreach。 从数组中选择特定值并将其用作显示循环的参数

Question

I want to be able to display titles of the books of the author who is currently logged in. I'm using PHP session

<? foreach ($books as $book ): ?>

<? foreach ($book as $selbook => $author): ?>
    <option value="$selbook>"$author['author'] == $_SESSION["sess_username"] ? ' selected="selected"' : ''?>> $author?></option>

<li class="active"><a href=""><span class="pull-right"><input id="button" type="submit" name="submitr" value="Edit"></span><i class="icon-fire$
<? echo htmlspecialchars($book['Title'], ENT_QUOTES, 'UTF-8'); ?> <strong> - </strong><em>
<? echo htmlspecialchars($book['author'], ENT_QUOTES, 'UTF-8');?></em></a></li>
<? endforeach; ?>
<? endforeach; ?>

Answer 1

You start 2nd foreach with this:

<?php foreach ($book as $selbook => $author) { ?>

And end with this:

<?php endforeach; ?>

It is not correct. Use this:

<?php foreach ($book as $selbook => $author): ?>
    // some code
<?php endforeach; ?>

Also, why u use <?php? Short tag is not enabled? Use <? it is much faster to write and code is more readable. Also, when you want to echo some variable, using php tag use this:

<?=$variable;?>

Much faster and more readable too.

Update

Try this:

<? foreach ($books as $book ): ?>
 <? foreach ($book as $selbook => $author): ?>
  <option value="<?=$selbook;?>" <? if($author['author'] == $_SESSION["sess_username"]): ?>selected="selected"<? endif; ?> ><?=$author;?></option>

  <li class="active"><a href=""><span class="pull-right"><input id="button" type="submit"  name="submitr" value="Edit"></span><i class="icon-fire$
  <? echo htmlspecialchars($book['Title'], ENT_QUOTES, 'UTF-8'); ?> <strong> - </strong><em>
  <? echo htmlspecialchars($book['author'], ENT_QUOTES, 'UTF-8');?></em></a></li>
 <? endforeach; ?>
<? endforeach; ?>