Regex 如何设置此正则表达式的最大长度？

这种验证对于允许字母数字字符、空格和破折号非常有效，但我无法将最大长度设置为23

正则表达式： （^\w+\s*（？）（\s*\w+\s*）（\w+$）{0,23}

我需要通过的案例：

• 温斯顿1-6
• 温斯顿塞勒姆
• 温斯顿塞勒姆
• 1-2-3
• 带空格的单词2

我需要失败的案例：

• -纽伯蒂洛斯酒店-
• 123456789012134567890123444

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正则表达式无法按照您的要求计算匹配的总长度

使用

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并在匹配后手动检查组#1的长度。

单独检查长度可能更方便，但您可以使用前瞻来确认整个表达式在0到23个字符之间

(?=^.{0,23}$)(^\w+\s*(-?)(\s*\w+\s*)(\w+)$)

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只需使用前瞻来声明最大长度：

(?=^.{1,23}$)^\w+\s*(-?)(\s*\w+\s*)(\w+)$

或者，消极的前瞻也会起作用：

(?!^.{24,})^\w+\s*(-?)(\s*\w+\s*)(\w+)$

现代正则表达式支持可变宽度

^(?!(^-|-$|.{24,})).*

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演示

正则表达式解释：

^(?!(^-|-$|.{24,})).*

Assert position at the beginning of the string «^»
Assert that it is impossible to match the regex below starting at this position (negative lookahead) «(?!(^-|-$|.{24,}))»
   Match the regex below and capture its match into backreference number 1 «(^-|-$|.{24,})»
      Match this alternative «^-»
         Assert position at the beginning of the string «^»
         Match the character “-” literally «-»
      Or match this alternative «-$»
         Match the character “-” literally «-»
         Assert position at the end of the string, or before the line break at the end of the string, if any «$»
      Or match this alternative «.{24,}»
         Match any single character that is NOT a line break character «.{23,}»
            Between 24 and unlimited times, as many times as possible, giving back as needed (greedy) «{24,}»
Match any single character that is NOT a line break character «.*»
   Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»

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您没有尝试设置最大长度。您说过要将整个表达式从0到23次匹配，而不是将最大长度设置为23个字符。根据您所做的工作，最好只单独检查字符串的长度，尽管您应该能够执行

（？=^.{0,23}$）

您使用的是哪种语言？OP是否指定了Perl正则表达式？这不会在任何地方都得到支持，不是吗？

Winston1-Salem6 - PASS
Winston-Salem - PASS
Winston Salem - PASS
1-two3 - PASS
word2 with space - PASS
-Newberty-Los-  - FAIL 
12345678901234567890123444 - FAIL

^(?!(^-|-$|.{24,})).*

Assert position at the beginning of the string «^»
Assert that it is impossible to match the regex below starting at this position (negative lookahead) «(?!(^-|-$|.{24,}))»
   Match the regex below and capture its match into backreference number 1 «(^-|-$|.{24,})»
      Match this alternative «^-»
         Assert position at the beginning of the string «^»
         Match the character “-” literally «-»
      Or match this alternative «-$»
         Match the character “-” literally «-»
         Assert position at the end of the string, or before the line break at the end of the string, if any «$»
      Or match this alternative «.{24,}»
         Match any single character that is NOT a line break character «.{23,}»
            Between 24 and unlimited times, as many times as possible, giving back as needed (greedy) «{24,}»
Match any single character that is NOT a line break character «.*»
   Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»