php 使用 preg_replace 删除所有非字母数字字符
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/11321048/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Remove all non-alphanumeric characters using preg_replace
提问by lisovaccaro
How can I remove all non alphanumeric characters from a string in PHP?
如何从 PHP 中的字符串中删除所有非字母数字字符？
This is the code, that I'm currently using:
这是我目前正在使用的代码：
$url = preg_replace('/\s+/', '', $string);
It only replaces blank spaces.
它只替换空格。
回答by John Conde
$url = preg_replace('/[^\da-z]/i', '', $string);
回答by sevenadrian
At first take this is how I'd do it
起初，这就是我要做的
$str = 'qwerty!@#$@#$^@#$Hello%#$';
$outcome = preg_replace("/[^a-zA-Z0-9]/", "", $str);
var_dump($outcome);
//string(11) "qwertyHello"
Hope this helps!
希望这可以帮助！
回答by Chuck Le Butt
Not sure why no-one else has suggested this, but this seems to be the simplest regex:
不知道为什么没有其他人提出这个建议，但这似乎是最简单的正则表达式：
preg_replace("/\W|_/", "", $string)
You can see it in action here, too: http://phpfiddle.org/lite/code/0sg-314
你也可以在这里看到它的实际效果：http: //phpfiddle.org/lite/code/0sg-314
回答by Damith Ruwan
You can use,
您可以使用，
$url = preg_replace('/[^\da-z]/i', '', $string);
You can use for unicode characters,
您可以使用 unicode 字符，
$url = preg_replace("/[^[:alnum:][:space:]]/u", '', $string);
回答by lisovaccaro
preg_replace('/[\s\W]+/', '', $string)
Seems to work, actually the example was in PHP documentation on preg_replace
似乎有效，实际上该示例在 preg_replace 的 PHP 文档中
回答by Alix Axel
$alpha = '0-9a-z'; // what to KEEP
$regex = sprintf('~[^%s]++~i', preg_quote($alpha, '~')); // case insensitive
$string = preg_replace($regex, '', $string);
