PHP regular does not contain a certain string sample code

This article introduces how to write PHP regular expressions that do not contain a certain string. Examples of regular expressions that do not contain a specified string. Friends in need can refer to it.

In PHP programming, the common function for matching strings is strstr($str, “abc”); Regular matching

preg_match(”/(abc)?/is”, $str);

But if you want to match a string that does not contain a certain string, it is more troublesome to use regular expressions. The problem can be solved if the regular expression !strstr($str, “abc”); is not used.

Use regular names like this:

"/^((?!abc).)*$/is"

Example:

The result is: 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 the return value of $arr is 2; Matches both the string "abc" and not the string "xyz"

"/(abc)[^((?!xyz).)*$]/s"