preg_match（）失败了

Question

I need to check if a string contains a table, which is like this:

+--------+------+-------+
| <info>number</info> | <info>char</info> | <info>word</info>  |
+--------+------+-------+
| 1      | a    | alfa  |
| 2      | b    | beta  |
| 3      | c    | gamma |
+--------+------+-------+

I do not know the number of columns, nor the number of rows, but this is the structure of the table.

This regex works with Unix, but not with Windows

[\+\-]+[
](\|(\s+<info>[^<]+<\/info>\s+\|)+)[
](\+|\-)+[
]((\|(\s+[^\|]+\s+\|)+[
])+)(\+|\-)+

This is a test:
https://regex101.com/r/TSxSd7/1

And this is a part of code:

    $regexRowDivider = '[\+\-]+';
    $regexHeader = '(\|(\s+<info>[^<]+<\/info>\s+\|)+)';
    $regexRow = '\|(\s+[^\|]+\s+\|)+';
    $regexRows = '((' . $regexRow . '[
])+)';
    $regexTable = $regexRowDivider . '[
]' . $regexHeader . '[
]' . $regexRowDivider . '[
]' . $regexRows . $regexRowDivider;

    preg_match('/' . $regexTable . '/', $output, $matches);

After hours of testing, I can not figure out what the problem is. Do you have any idea? preg_last_error() returns a 0 (no errors)

Answer 1

This is probably because you're only accepting one of either or , and Windows uses both ( ). You can match both of these newline characters (and more) by using \R.

I removed a few pieces of complexity, so it doesn't enforce spaces in every cell:

[+-]+\R+\|(\s*<info>[^<]+<\/info>\s*\|)+\R+[+-]+\R+\|([^|]+\|)+\R+[+-]+

\---/   \------------------------------/   \---/   \----------/   \---/
Line             Column Headers            Line      Contents     Line

Try it online