---------who_are_you.php <html> <head> <title> Who Are You ? </title> <style> <!-- body,td,input,p{font-size:12px} --> </style> </head><body> <form action="you_are.php" method="get"> Please enter your name:<br /> I am... <?php print('<input type="text" name="person" value="'.$_GET['person'].'" size="15" />'); ?> <input type="submit" value="Go!" /> </form> </body> </html>-------------you_are.php <html> <head> <title> You Are... </title> <style> <!-- body,td,input,p{font-size:12px} --> </style> </head><body> <?php print('Well,hello<b><font color="#ff0000">'.urldecode($_GET['person']).'</font></b>,nice to meet you!'); print('<br />'); print('<a href="who_are_you.php?person='.urlencode($_GET['person']).'">Back to Who Are You ?</a>'); ?> </body> </html>第一次运行时浏览器提示:Notice: Undefined index: person in c:\inetpub\wwwroot\myphp\old\index.php on line 16第一次运行时$person变量未被定义,怎样才能定义呢??
1、只有在类定义中才需要使用var声明类的属性 2、.... <?php if(isset($_GET['person'])) print('<input type="text" name="person" value="'.$_GET['person'].'" size="15" />'); ?> .... <?php if(isset($_GET['person'])) { print('Well,hello<b><font color="#ff0000">'.urldecode($_GET['person']).'</font></b>,nice to meet you!'); print('<br />'); print('<a href="who_are_you.php?person='.urlencode($_GET['person']).'">Back to Who Are You ?</a>'); } ?>
<html>
<head>
<title> Who Are You ? </title>
<style>
<!--
body,td,input,p{font-size:12px}
-->
</style>
</head><body>
<form action="you_are.php" method="get">
Please enter your name:<br />
I am...
<?php
print('<input type="text" name="person" value="'.$_GET['person'].'" size="15" />');
?>
<input type="submit" value="Go!" />
</form>
</body>
</html>-------------you_are.php
<html>
<head>
<title> You Are... </title>
<style>
<!--
body,td,input,p{font-size:12px}
-->
</style>
</head><body>
<?php
print('Well,hello<b><font color="#ff0000">'.urldecode($_GET['person']).'</font></b>,nice to meet you!');
print('<br />');
print('<a href="who_are_you.php?person='.urlencode($_GET['person']).'">Back to Who Are You ?</a>');
?>
</body>
</html>第一次运行时浏览器提示:Notice: Undefined index: person in c:\inetpub\wwwroot\myphp\old\index.php on line 16第一次运行时$person变量未被定义,怎样才能定义呢??
2、....
<?php
if(isset($_GET['person']))
print('<input type="text" name="person" value="'.$_GET['person'].'" size="15" />');
?>
....
<?php
if(isset($_GET['person'])) {
print('Well,hello<b><font color="#ff0000">'.urldecode($_GET['person']).'</font></b>,nice to meet you!');
print('<br />');
print('<a href="who_are_you.php?person='.urlencode($_GET['person']).'">Back to Who Are You ?</a>');
}
?>