Regex 用于提取第一组+；第二组或第一组（仅当无第二组时）（包括变化）
最好的解释方式是准确地展示我希望实现的目标：Regex 用于提取第一组+；第二组或第一组（仅当无第二组时）（包括变化）,regex,Regex,最好的解释方式是准确地展示我希望实现的目标： 案例1：“搜索波士顿芬威公园” 摘录：第1组--> “芬威公园”，第二组-->“波士顿” 案例2：“搜索芬威公园” 摘录：第1组-->“芬威 停车场“ 请注意，在这两种情况下，我都希望能够适应“搜索”（“查找”，“查找”，等等）和“在”（“在”，“周围”，等等）的变化。 我尝试了许多不同的变体，但要么在第1组提取了“波士顿芬威公园”，而在第2组中没有提取任何内容，要么如果我正确理解了案例1，案例2将不起作用。这应该对您有用 ^(?:search
- 案例1：
“搜索波士顿芬威公园”
摘录：第1组-->
，第二组-->“芬威公园”“波士顿” - 案例2：
“搜索芬威公园”
摘录：第1组-->“芬威 停车场“
“搜索”“查找”“查找”“在”“在”“周围”我尝试了许多不同的变体，但要么在第1组提取了
“波士顿芬威公园”^(?:search for|look for|find)\s*(.*?)(?:\s*(?:in|around|at)\s*(.*))?$
查找/in/at@"
^ # Assert position at the beginning of a line (at beginning of the string or after a line break character)
(?: # Match the regular expression below
# Match either the regular expression below (attempting the next alternative only if this one fails)
search\ for # Match the characters “search for” literally
| # Or match regular expression number 2 below (attempting the next alternative only if this one fails)
look\ for # Match the characters “look for” literally
| # Or match regular expression number 3 below (the entire group fails if this one fails to match)
find # Match the characters “find” literally
)
\s # Match a single character that is a “whitespace character” (spaces, tabs, and line breaks)
* # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
( # Match the regular expression below and capture its match into backreference number 1
. # Match any single character that is not a line break character
*? # Between zero and unlimited times, as few times as possible, expanding as needed (lazy)
)
(?: # Match the regular expression below
\s # Match a single character that is a “whitespace character” (spaces, tabs, and line breaks)
* # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
(?: # Match the regular expression below
# Match either the regular expression below (attempting the next alternative only if this one fails)
in # Match the characters “in” literally
| # Or match regular expression number 2 below (attempting the next alternative only if this one fails)
around # Match the characters “around” literally
| # Or match regular expression number 3 below (the entire group fails if this one fails to match)
at # Match the characters “at” literally
)
\s # Match a single character that is a “whitespace character” (spaces, tabs, and line breaks)
* # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
( # Match the regular expression below and capture its match into backreference number 2
. # 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)
)
)? # Between zero and one times, as many times as possible, giving back as needed (greedy)
$ # Assert position at the end of a line (at the end of the string or before a line break character)
"
这应该对你有用
^(?:search for|look for|find)\s*(.*?)(?:\s*(?:in|around|at)\s*(.*))?$
查找/in/at@"
^ # Assert position at the beginning of a line (at beginning of the string or after a line break character)
(?: # Match the regular expression below
# Match either the regular expression below (attempting the next alternative only if this one fails)
search\ for # Match the characters “search for” literally
| # Or match regular expression number 2 below (attempting the next alternative only if this one fails)
look\ for # Match the characters “look for” literally
| # Or match regular expression number 3 below (the entire group fails if this one fails to match)
find # Match the characters “find” literally
)
\s # Match a single character that is a “whitespace character” (spaces, tabs, and line breaks)
* # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
( # Match the regular expression below and capture its match into backreference number 1
. # Match any single character that is not a line break character
*? # Between zero and unlimited times, as few times as possible, expanding as needed (lazy)
)
(?: # Match the regular expression below
\s # Match a single character that is a “whitespace character” (spaces, tabs, and line breaks)
* # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
(?: # Match the regular expression below
# Match either the regular expression below (attempting the next alternative only if this one fails)
in # Match the characters “in” literally
| # Or match regular expression number 2 below (attempting the next alternative only if this one fails)
around # Match the characters “around” literally
| # Or match regular expression number 3 below (the entire group fails if this one fails to match)
at # Match the characters “at” literally
)
\s # Match a single character that is a “whitespace character” (spaces, tabs, and line breaks)
* # Between zero and unlimited times, as many times as possible, giving back as needed (greedy)
( # Match the regular expression below and capture its match into backreference number 2
. # 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)
)
)? # Between zero and one times, as many times as possible, giving back as needed (greedy)
$ # Assert position at the end of a line (at the end of the string or before a line break character)
"
谢谢你的详细回答。不幸的是，我得到了相同的结果：它适用于“搜索波士顿芬威公园”，并正确地分别提取每个组，但不匹配“搜索芬威公园”中的任何内容，因为“in | around | at”组不是可选的。如果我将其设置为可选，则所有内容都在一个组中匹配（不是我想要的）。@BlazingFrog更新了正则表达式。现在检查一下，太棒了！我现在明白了我认为做错了什么：我把这两个组（“on | in”和“boston”）都设置为可选的，但分开设置。您将这两个组都包含在一个组中，并使该组成为可选组，看起来它成功了。再次感谢。如果我能投票两次，我会的！棒极了。我唯一的更改是将两个\s*都更改为\s+——否则您可以匹配“无空格”，并发现“search for Fenway parkin boston”匹配。@谢谢您的评论。我在想你提到的
\s+\s*\s+\s*