如何验证正则表达式? [英] How can I validate regex?

问题描述

我想在PHP中测试正则表达式的有效性，最好在使用前进行测试.这样做的唯一方法是实际尝试preg_match()并查看它是否返回FALSE吗?

I'd like to test the validity of a regular expression in PHP, preferably before it's used. Is the only way to do this actually trying a preg_match() and seeing if it returns FALSE?

是否有更简单/正确的方法来测试有效的正则表达式?

Is there a simpler/proper way to test for a valid regular expression?

推荐答案

// This is valid, both opening ( and closing )
var_dump(preg_match('~Valid(Regular)Expression~', null) === false);
// This is invalid, no opening ( for the closing )
var_dump(preg_match('~InvalidRegular)Expression~', null) === false);

正如用户 pozs 所说，还考虑在测试环境中将@放在preg_match()(@preg_match())前面，以防止发出警告或通知.

As the user pozs said, also consider putting @ in front of preg_match() (@preg_match()) in a testing environment to prevent warnings or notices.

要验证RegExp，只需针对null (无需知道您要预先测试的数据)运行它即可..如果返回显式false(=== false)，则表示它已损坏.否则它是有效的，尽管它不需要匹配任何内容.

To validate a RegExp just run it against null (no need to know the data you want to test against upfront). If it returns explicit false (=== false), it's broken. Otherwise it's valid though it need not match anything.

因此无需编写自己的RegExp验证器. 这是浪费时间...

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