PHP @ at 记号的作用示例介绍,at示例
PHP @ at 记号的作用示例介绍,at示例
看PHP的代码,总有些行前边有@符号,一直不知道是什么意思。 例如dede5.7 @ni=imagecreatetruecolor(ftoW,$ftoH);
今天用到了,就记一下吧。其实它是错误控制符,即即使出现错误,也无视出现的错误信息,继续执行下边的代码。
@$page=$_GET['page']?intval($_GET['page']):1;
这句是从URL中获取page关键字的值,比如"index.php?page=5",则$page就会取到5。
但是如果有error,比如"index.php"后没有page关键字了,如果去取$_GET['page']不存在就会报错,这时有@就可以忽视这个小错误了。
又比如:
$conn = mysqli_conncet("q","w","e","r");
这样会输入错误信息,关于连接数据库方面的。
如果$conn前面加@的话就可以不让他输出错误信息了。
@$conn = mysqli_conncet("q","w","e","r");
这里随便记一下。
short_open_tag = On
这样才对。你要把那一行开头的分号去掉。分号的意思是,“这一行是注释,不产生作用”。
echo phpinfo();?> 怎么不能输出 apcha 都已经启动 路径全部设置好
若用 就可以输出
那当然啊。你短标记都没打开,那就只有之间的内容会被显示。
记得用
^ 是php 正则里面的一个开始匹配标记
$preg = '/^a/';//匹配 以a开始的字符

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