Hello,
how could I remove all characters from a string that aren't a-z/A-Z and 0-9 and _ with PHP?
I tried that but it has no effect, it returns the same string back:
preg_replace('[^a-zA-Z0-9_]', '', 'Testdo123_-:=)§%&');
views:
32answers:
2
+1
A:
It seems you're forgetting delimiters:
preg_replace('/\W+/', '', 'Testdo123_-:=)§%&');
\W stands for [^a-zA-Z0-9_]
SilentGhost
2010-05-11 14:40:59
`\W` means all characters that are **not** word characters (maybe you should add an explanation).
Felix Kling
2010-05-11 14:43:22
@Tim: he doesn't use delimiters, I'd guess
SilentGhost
2010-05-11 14:44:33
Note that `\w` and its complement `\W` depend on the locale that is used.
Gumbo
2010-05-11 14:46:45
+3
A:
The preg_ prefixed functions require PCRE styled regular expression that use delimiters to separate the regular expression from optional flags/modifiers.
But you forgot delimiters. Or, to be precise: PHP takes the [ and ] as delimiters, leaving just ^a-zA-Z0-9_ as your actual regular expression.
So try this (using / as delimiters):
preg_replace('/[^a-zA-Z0-9_]/', '', 'Testdo123_-:=)§%&')
Gumbo
2010-05-11 14:43:09