javascript - 正则表达式 : Match a string enclosed in single quotes but don't match those inside double quotes

Question

我想编写一个正则表达式来匹配用单引号括起来的字符串，但不应该匹配用双引号括起来的带有单引号的字符串。

示例 1:

a = 'This is a single-quoted string';

a 的整个值应该匹配，因为它用单引号括起来。

编辑:完全匹配应该是: '这是一个单引号字符串'

示例 2:

x = "This is a 'String' with single quote";

x 不应返回任何匹配项，因为单引号位于双引号内。

我试过 /'.*'/g 但它也匹配双引号字符串中的单引号字符串。

感谢您的帮助!

编辑:

为了更清楚

给定以下字符串:

The "quick 'brown' fox" jumps
over 'the lazy dog' near
"the 'riverbank'".

匹配应该只是:

'the lazy dog'

Answer 1

假设不必处理转义引号(这是可能的，但会使正则表达式复杂化)，并且所有引号都正确平衡(不像 It's... "Monty Python's Flying Circus"! )，那么您可以查找后跟偶数个双引号的单引号字符串:

/'[^'"]*'(?=(?:[^"]*"[^"]*")*[^"]*$)/g

查看live on regex101.com .

解释:

'        # Match a '
[^'"]*   # Match any number of characters except ' or "
'        # Match a '
(?=      # Assert that the following regex could match here:
 (?:     # Start of non-capturing group:
  [^"]*" # Any number of non-double quotes, then a quote.
  [^"]*" # The same thing again, ensuring an even number of quotes.
 )*      # Match this group any number of times, including zero.
 [^"]*   # Then match any number of characters except "
 $       # until the end of the string.
)        # (End of lookahead assertion)