PHP strpos check against many

问题:

I am looking to use strpos to check for many chars in a string, for example:

I would like to separately check for the chars :,!, and & in $string. If any of them are found at any point, return false.

What's the most efficient way to do so? Thanks!

回答1:

Use preg_match

preg_match("/[:!&]/", $string) !== 1;

Example:

var_dump(preg_match("/[:!&]/", "this is !a test string"));
> int(1)
var_dump(preg_match("/[:!&]/", "this is a test string"));
> int(0)

preg_match() returns 1 if the pattern matches given subject, 0 if it does not, or FALSE if an error occurred.

回答2:

If any of them are found, return false.

Since you don't care about the actual position of the character, you could use regex:

preg_match("/[:!&]/", $str); // 1 if found, 0 if none found

回答3:

If your post is accurate and what you are trying to do is return FALSE if those strings are found, strpos() is not the right function. strpos() is to find where in a string certain characters (or strings) first appear.

If your stated goal is accurate, you probably want something more like this:

if( preg_match( "/[\:\!&]/", $str ) > 0 ) { return false; }