使用正则表达式从文本中提取未知数量的字符串

Question

I´m using regular expressions in order to extract certain information from a text. A name, for example, can consist of several first names and a last name (quantity not known). The following example extracts 2 strings:

Name:\s+([\w-äöü]+\s[\w-äöü]+)

How can define regular expressions in order to extract an unknown (!) amount of string, up to a defined next term (eg "Address:")?

Answer 1

Use

Name:\s+([\wäöü-]+(?:\s+[\wäöü-]+)*?)(?=\s*Address)

See proof .

Explanation

--------------------------------------------------------------------------------
  Name:                    'Name:'
--------------------------------------------------------------------------------
  \s+                      whitespace (\n, \r, \t, \f, and " ") (1 or
                           more times (matching the most amount
                           possible))
--------------------------------------------------------------------------------
  (                        group and capture to \1:
--------------------------------------------------------------------------------
    [\wäöü-]+                any character of: word characters (a-z,
                             A-Z, 0-9, _), 'ä', 'ö', 'ü', '-' (1 or
                             more times (matching the most amount
                             possible))
--------------------------------------------------------------------------------
    (?:                      group, but do not capture (0 or more
                             times (matching the least amount
                             possible)):
--------------------------------------------------------------------------------
      \s+                      whitespace (\n, \r, \t, \f, and " ")
                               (1 or more times (matching the most
                               amount possible))
--------------------------------------------------------------------------------
      [\wäöü-]+                any character of: word characters (a-
                               z, A-Z, 0-9, _), 'ä', 'ö', 'ü', '-' (1
                               or more times (matching the most
                               amount possible))
--------------------------------------------------------------------------------
    )*?                      end of grouping
--------------------------------------------------------------------------------
  )                        end of \1
--------------------------------------------------------------------------------
  (?=                      look ahead to see if there is:
--------------------------------------------------------------------------------
    \s*                      whitespace (\n, \r, \t, \f, and " ") (0
                             or more times (matching the most amount
                             possible))
--------------------------------------------------------------------------------
    Address                  'Address'
--------------------------------------------------------------------------------
  )                        end of look-ahead