非常重要的php函数htmlspecialchars

<?php

$str = "This is some <b>bold</b> text.";

$str = "This is some <b>bold</b> text.";

$str = "This is some <b>bold</b> text.";

$str = "你好 世界 <b>bold</b> text.";

echo htmlspecialchars($str);