regex - 仅当先前的组匹配将捕获设置为空时才捕获条件正则表达式？

Question

试图让条件正则表达式工作以使用https://regex101.com/r/51mp2i/1中的 2 个事件捕获域和用户代理值， 但仅获得 1 个匹配项。如何使用条件正则表达式更新正则表达式以获取 2 个匹配项？谢谢。

Match 1:
domain: example.org
useragent: "" or not capture
Match 2:
domain: example.org
useragent: Mozilla/5.0 (compatible;example-checks/1.0;+https://www.example.com/; check-id: 9EXc112795a4766a)

标签： regex

Answer 1

采用

"headers":\s+\[{"name":\s+"Host",\s+"value":\s+"(?<domain>[^"]+)(?:.*?"(?i)User-?(?i)Agent",\s+"value":\s+"(?<useragent>[^"]*))?

见证明。

解释

--------------------------------------------------------------------------------
  "headers":               '"headers":'
--------------------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
--------------------------------------------------------------------------------
  \[                       '['
--------------------------------------------------------------------------------
  {"name":                 '{"name":'
--------------------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
--------------------------------------------------------------------------------
  "Host",                  '"Host",'
--------------------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
--------------------------------------------------------------------------------
  "value":                 '"value":'
--------------------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
--------------------------------------------------------------------------------
  "                        '"'
--------------------------------------------------------------------------------
  (                        group and capture to \1:
--------------------------------------------------------------------------------
    [^"]+                    any character except: '"' (1 or more
                             times (matching the most amount
                             possible))
--------------------------------------------------------------------------------
  )                        end of \1
--------------------------------------------------------------------------------
  (?:                      group, but do not capture (optional
                           (matching the most amount possible)):
--------------------------------------------------------------------------------
    .*?                      any character except \n (0 or more times
                             (matching the least amount possible))
--------------------------------------------------------------------------------
    "User                    '"User'
--------------------------------------------------------------------------------
    -?                       '-' (optional (matching the most amount
                             possible))
--------------------------------------------------------------------------------
    Agent",                  'Agent",'
--------------------------------------------------------------------------------
    \s+                      whitespace (\n, \r, \t, \f, and " ") (1
                             or more times (matching the most amount
                             possible))
--------------------------------------------------------------------------------
    "value":                 '"value":'
--------------------------------------------------------------------------------
    \s+                      whitespace (\n, \r, \t, \f, and " ") (1
                             or more times (matching the most amount
                             possible))
--------------------------------------------------------------------------------
    "                        '"'
--------------------------------------------------------------------------------
    (                        group and capture to \2:
--------------------------------------------------------------------------------
      [^"]*                    any character except: '"' (0 or more
                               times (matching the most amount
                               possible))
--------------------------------------------------------------------------------
    )                        end of \2
--------------------------------------------------------------------------------
  )?                       end of grouping