提高我的正则表达能力
我想提高我的正则表达式技能已经有一段时间了，并且“掌握正则表达式”被推荐了很多次，所以我买了它并在过去一天左右的时间里一直在阅读它。
我创建了以下正则表达式：
^(?:<b>)?(?:^<i>)?<a href="/site\.php\?id=([0-9]*)">(.*?) \(([ a-z0-9]{2,10})\)</a>(?:^</i>)?(?:</b>)?$
它匹配前两个链接，但忽略 标记包含的两个链接。 它提取 id、标题和类型。
<a href="/site.php?id=6321">site 1 title (type 1)</a>
<b><a href="/site.php?id=10254">site 2 title (type 2)</a></b>
<i><a href="/site.php?id=5479">site 3 title (type 3)</a></i>
<b><i><a href="/site.php?id=325">site 4 title (type 4)</a></i></b>
虽然它有效，但对于这么简单的东西来说似乎相当长，它可以改进吗？
I've been wanting to improve my regex skills for quite some time now and "Mastering Regular Expressions" was recommended quite a few times so I bought it and have been reading it over the past day or so.
I have created the following regular expression:
^(?:<b>)?(?:^<i>)?<a href="/site\.php\?id=([0-9]*)">(.*?) \(([ a-z0-9]{2,10})\)</a>(?:^</i>)?(?:</b>)?$
Which matches the first two links but ignores the two enclosed by an <i> tag.
It extracts the id, title and type.
<a href="/site.php?id=6321">site 1 title (type 1)</a>
<b><a href="/site.php?id=10254">site 2 title (type 2)</a></b>
<i><a href="/site.php?id=5479">site 3 title (type 3)</a></i>
<b><i><a href="/site.php?id=325">site 4 title (type 4)</a></i></b>
Although it works, it seems fairly long for something so simple, could it be improved?
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由于缺少使用字符类（\d 表示 0-9 等），我不认为有问题的正则表达式可以缩短很多； 然而...
顺便说一句，值得一提的是，用正则表达式解析 HTML 充其量是危险的； 当处理 HTML（以及较小程度上的 XML）时，DOM 工具通常更适合。
Short of using character classes (\d for 0-9 etc.) I don't see that the regular expression in question could be shortened much; however...
As a side note it can be worth mentioning that parsing HTML with regular expressions is hazardous at best; when dealing with HTML (and to a lesser extent XML), DOM tools are generally better suited.
如果你像Whilliham那样编写屏幕截图，正确地提到DOM可能是正则表达式的合适解析器，因为HTML比正则表达式更宽容。
没有缩短太多，但正则表达式更宽容一点
字符串检查，你真的需要吗
他们？
前面不会出现(?)(.*?) \(([ az\d]{2 ,})\)If your writing screenscrappers as Whilliham rightfully mentions DOM might just be a suitable parser as Regex since HTML is alot more forgiving then regex.
Not shortened by much but a bit the regex is more forgiving
string checks, did you really need
them?
<a>is not preceeded by<i>(?<!<i>)<a href="/site.php\?id=(\d*)">(.*?) \(([ a-z\d]{2,})\)