javascript - JS中的正则表达式（从字符串中选择标签）

Question

我有这个字符串：

some description +first tag, +second tag (tags separated by commas)
+third tag +fourth tag (tags separated by space)
+tag from new line (it's just one tag)
+tag1+tag2+tag3 (tags can follow each other)

如何从此字符串中选择所有标签名称？

1) 标签可以包含多个单词，2) 标签始终以 + 号开头，3) 标签以下一个标签、换行符或逗号结尾

Answer 1

我试一试：

var str = "some description +first tag, +second tag\n" +
   "+third tag +fourth tag\n" +
   "+tag from new line\n" +
   "+tag1+tag2+tag3";
var tags = str.match(/\+[^+,\n\s].+?(?=\s*[\+,\n]|$)/g);

这导致tags：

[ '+first tag',
  '+second tag',
  '+third tag',
  '+fourth tag',
  '+tag from new line',
  '+tag1',
  '+tag2',
  '+tag3' ]

详细说明：

\+          // Starts with a '+'.
[^+,\n\s]   // Doesn't end immedatedly (empty tag).
.+?         // Non-greedily match everything.
(?=         // Forward lookahead (not returned in match).
  \s*       // Eat any trailing whitespace.
  [\+,\n]|$ // Find tag-ending characters, or the end of the string.
)