我不想在一个字符串中允许多个模式,例如,
$string = "php in stackoverflow"; // multiple spaces not allowed
$string = "php in--stackoverflow"; // multiple hyphens not allowed
$string = "php in__stackoverflow"; // multiple underscores not allowed
etc
字符串
所以,它可以用这些线,
if(preg_match('/\s\s+/', $string)) echo "only a single spaces are allowed";
if(preg_match('/\-\-+/', $string)) echo "only a single hyphens are allowed";
if(preg_match('/\_\_+/', $string)) echo "only a single underscores are allowed";
型
我也不想让下面的组合模式和上面的线条不起作用,
$string = "php in -stackoverflow"; // a space with a hyphen not allowed
$string = "php in-_stackoverflow"; // a hyphens with a underscore not allowed
$string = "php in_ stackoverflow"; // a underscore with a space not allowed
etc
型
有没有办法用一个简单的脚本来实现这一点?
1条答案
按热度按时间gkn4icbw1#
这就是字符类的作用,匹配多个字符。
字符串