<!DOCTYPE html>
<html>
<body>
<?php
$x = 75;
$y = 25;
function addition()
{
$GLOBALS['z'] = $GLOBALS['x'] + $GLOBALS['y'];
}
addition();
echo $z;
?>
</body>
</html>
<!DOCTYPE html>
<html>
<body>
<?php
echo $_SERVER['PHP_SELF'];
echo "<br>";
echo $_SERVER['SERVER_NAME'];
echo "<br>";
echo $_SERVER['HTTP_HOST'];
echo "<br>";
echo $_SERVER['HTTP_REFERER'];
echo "<br>";
echo $_SERVER['HTTP_USER_AGENT'];
echo "<br>";
echo $_SERVER['SCRIPT_NAME'];
?>
</body>
</html>
<!DOCTYPE html>
<html>
<body>
<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
Name: <input type="text" name="fname">
<input type="submit">
</form>
<?php
$name = htmlspecialchars($_REQUEST['fname']);
echo $name;
?>
</body>
</html>
<!DOCTYPE html>
<html>
<body>
<a href="test_get.php?subject=PHP&web=runoob.com">测试 $_GET</a>
</body>
</html>
