正则表达式匹配标签是否有关闭标签？

Question

I am struggling with detect these patterns in a content body:

   [tagname blah blah blah]blah blah blah[/tagname]  // pattern 1: with close tag

   [tagname blah blah blah]   //pattern 2: without close tag

Pattern examples:

[vimeo align='center' id='123']//player.vimeo.com/video/123[/vimeo]

[vimeo align='left' id='123']

Right now I came up with this regular expression capturing both:

/\[(?<name>vimeo)[^\]]+\](?:(.*?)\[\/\g<name>\])?/

Notice there is a ? at the end of (?:(.*?)\[\/\g<name>\]) to make the subpattern optional. But there is a problem with this. It will falsely match [vimeo align='center' id='123']//player.vimeo.com/video/123[/youtube] (notice the closing tag is youtube not vimeo now)

Can anyone help me to fix this regular expression? Thanks!

Answer 1

You can use this regex:

\[(?<name>vimeo)[^\]]+\](?:(.*?)\[\/\g<name>\]|(?![^[]*\[\/))

instead of making the end tag optional, I'll look foward to check if there isn't anty closing tag

Regex101