PHP 前加at符合@的作用解析_PHP
大家在做PHP项目时,总是有些代码行前加上@符号,大家都知道是什么意思吗?下面给大家分享下PHP中函数前加at符合@的作用解析
今天用到了,就记一下吧。其实它是错误控制符,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。
代码如下:
@$page=$_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:
代码如下:
$conn = mysqli_conncet("q","w","e","r");
这样会输入错误信息,关于连接数据库方面的。
代码如下:
@$conn = mysqli_conncet("q","w","e","r");
如果$conn前面加@的话就可以不让他输出错误信息了。
这里随便记一下。
以上就是PHP 前加at符合@的作用解析,希望大家喜欢。

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