正则表达式多次匹配捕获组

Question

我想让正则表达式捕获两个分隔符之间的模式的所有实例。
一个字符模式的简化示例(目标:捕获第一个 b 和最后一个 x 之间的所有 z ):

bbxabbcbacbedbzbb
    ^^ ^  ^  ^  

应该捕获 5 b s。
我试过 .*x.*(b).*z.*只捕获最后一个 b . ( rubular )

Answer 1

用

(?:x|(?<!\A)\G).*?\Kb(?=.*z)

见 regex proof .
说明

--------------------------------------------------------------------------------
  (?:                      group, but do not capture:
--------------------------------------------------------------------------------
    x                        'x'
--------------------------------------------------------------------------------
   |                        OR
--------------------------------------------------------------------------------
    (?<!                     look behind to see if there is not:
--------------------------------------------------------------------------------
      \A                       the beginning of the string
--------------------------------------------------------------------------------
    )                        end of look-behind
--------------------------------------------------------------------------------
    \G                       where the last m//g left off
--------------------------------------------------------------------------------
  )                        end of grouping
--------------------------------------------------------------------------------
  .*?                      any character except \n (0 or more times
                           (matching the least amount possible))
--------------------------------------------------------------------------------
  \K                       match reset operator (omits matched text)
--------------------------------------------------------------------------------
  b                        'b'
--------------------------------------------------------------------------------
  (?=                      look ahead to see if there is:
--------------------------------------------------------------------------------
    .*                       any character except line breaks (0 or more times
                             (matching the most amount possible))
--------------------------------------------------------------------------------
    z                        'z'
--------------------------------------------------------------------------------
  )                        end of look-ahead