Php regular expressions do not contain a string sample code

Php regular expressions do not contain a string sample code

This article describes how to write a php regular expression that does not contain a certain string. a regular expression does not contain a specified string. For more information, see. In php programming, strstr ($ str, "abc"), a common function that matches strings, and regular matching Preg_match ("/(abc )? /Is ", $ str ); However, to match a string that does not contain a specific string, it is more difficult to use regular expressions! Strstr ($ str, "abc"); to solve the problem. The naming rules can be as follows: "/^ ((?! Abc).) * $/is" Example: Result: false, containing abc! $ Str = "2b3c4d5c "; Note: [^ (abc)] this syntax checks whether the characters in $ str are not in a B c one by one, Preg_match ("/[^ (abc)]/s", $ str, $ arr ); The character 2 is not in a B c, so $ arr returns 2. it matches with the string "abc" and does not contain the string "xyz" "/(Abc) [^ ((?! Xyz).) * $]/s"