PHP 带标点符号

Question

假设我有这个:

$hello = "Hello, is StackOverflow a helpful website!? Yes!";

我想去掉标点符号，输出为:

hello_is_stackoverflow_a_helpful_website_yes

我该怎么做？

Answer 1

# to keep letters & numbers
$s = preg_replace('/[^a-z0-9]+/i', '_', $s); # or...
$s = preg_replace('/[^a-z\d]+/i', '_', $s);

# to keep letters only
$s = preg_replace('/[^a-z]+/i', '_', $s); 

# to keep letters, numbers & underscore
$s = preg_replace('/[^\w]+/', '_', $s);

# same as third example; suggested by @tchrist; ^\w = \W
$s = preg_replace('/\W+/', '_', $s);

对于字符串

$s = "Hello, is StackOverflow a helpful website!? Yes!";

结果(对于所有示例)是

Hello_is_StackOverflow_a_helpful_website_Yes_

享受吧!