正则表达式：|（OR）条件不起作用

Question

Can't figure out why OR condition in my regexp isn't working.

    $str = "                            <li><a href=\"\" class=\"gateway-image\"><img src=\"<?=theme_url()?>/images/Cherry Credits.jpg\" alt=\"\"/></a></li>
                        <li><a href=\"\" class=\"gateway-image\"><img src=\"<?=theme_url()?>/images/gudangvoucher.jpeg\" alt=\"\" style=\"width: 140px!important\"/></a></li>";

    $regexp = '/^(.*\<li\>\<a href\=)(.*cherry|credits.*)$/im';
    preg_match($regexp, $str, $m);

It seems regexp is correct but it can't find string Cherry Credits.jpg as I expected. What is wrong?

Answer 1

You've written the expression using the start- and end-of-line anchors ^ and $ .

This doesn't match because your string continues on after cherry and there are additional characters between href= and credits .

You can either remove the line anchors:

(.*\<li\>\<a href\=)(.*cherry|credits.*)

Or you can move the trailing .* (and probably the leading .* ) outside of the capture group:

^(.*\<li\>\<a href\=).*(cherry|credits).*$

Answer 2

You need to remove the "$" sign at the end, because it will expect a end of line.

Try this:

^(.*\\<li\\>\\<a href\\=).*(cherry|credits)(\\.jpg)

You can use online testers like this site: https://regex101.com/ and check if you are doing OK.