一段关于浏览器传值出错的有关问题 -PHP Tutorial-php.cn

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一段关于浏览器传值出错的有关问题

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Jun 13, 2016 pm 01:21 PM

classgetphp

一段关于浏览器传值出错的问题
这样写了两行代码，用来捕捉浏览器传值：

文件名：showclass.php

PHP code

<!--

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-->
$p_class=$_GET[pclass];
echo $p_class;

然后输入网址：http://127.0.0.1/showclass.php?pclass=111
回车。

报错，内容如下：

Notice: Use of undefined constant pclass - assumed 'pclass' in D:\setup\xampp\htdocs\products\showclass.php on line 31
111

如何才能不报错？
（用修改PHP.INI的来关闭notic的方法不算，因为要考虑代码可移植性。谢谢）

------解决方案--------------------
if(isset($_GET['pclass'])){
$pclass=$_GET['pclass'];
}else{
$pclass='';
}

var_dump($pclass);
------解决方案--------------------
pclass 加引号
------解决方案--------------------
这个也是必须的,很多初学者都很喜欢省略，其实是捡了芝麻，丢了西瓜.

探讨

pclass 加引号

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