php代码应当安全、结构化、规范化和自适应

1.未优化过的php代码
<?
echo(”<p>Search results for query: ” .
$_GET['query'] . “.</p>”);
?>
2.简单优化过的代码
<?
echo(”<p>Search results for query: ” .
htmlspecialchars($_GET['query']) . “.</p>”);
?>
3.合理优化过的代码
<?php
if (isset($_GET['query']))
{
echo ‘<p>Search results for query: ‘,
htmlspecialchars($_GET['query'], ENT_QUOTES), ‘.</p>’;
}
?>