Question

我需要一个正则表达式的帮助来捕获以下字符串中的数字和连字符： “一些文字和东西200-1234EM其他一些东西”

它也可以在没有超级部分的情况下出现： “一些文字123EM其他文字”

我在命名捕获组中需要“200-1234”或“123”。

我试过这个： \b([0-9]{0,3}\-{0,1}[0-9]{3})EM\b

确实匹配，但它不是命名组。

当我尝试为此组命名时： \b(?<test>[0-9]{0,3}\-{0,1}[0-9]{3})EM\b我收到错误消息“索引34附近的未知后视组”

我需要这个在.NET RegEx类中工作

谢谢！

Answer 1

resultString = Regex.Match(subjectString, @"\b(?<number>\d+(?:-\d+)?)EM\b").Groups["number"].Value;

这应该可以解决问题。如果你提供更多输入，我可以使它更健壮。

<强>解释

    @"
\b            # Assert position at a word boundary
(?<number>    # Match the regular expression below and capture its match into backreference with name “number”
   \d            # Match a single digit 0..9
      +             # Between one and unlimited times, as many times as possible, giving back as needed (greedy)
   (?:           # Match the regular expression below
      -             # Match the character “-” literally
      \d            # Match a single digit 0..9
         +             # Between one and unlimited times, as many times as possible, giving back as needed (greedy)
   )?            # Between zero and one times, as many times as possible, giving back as needed (greedy)
)
EM            # Match the characters “EM” literally
\b            # Assert position at a word boundary
"

正则表达式中命名的捕获组

1 个答案: