1234 |
var re = /(\w+)\s(\w+)/;var str = 'John Smith';var newstr = str.replace(re, '$2, $1');console.log(newstr); // Smith, John |
$1 $2是指被括号()包起来的\w+。
即当要使用变量替换时，$n指第n个用()包起来的表达式的值。
要用()包起来呀…‘(>﹏<)′ ‘(>﹏<)′
Specifying a string as a parameter
The replacement string can include the following special replacement patterns:
| Pattern | Inserts |
|---|---|
| $$ | Inserts a “$”. |
| $& | Inserts the matched substring. |
| $` | Inserts the portion of the string that precedes the matched substring. |
| $’ | Inserts the portion of the string that follows the matched substring. |
| $n | Where n is a non-negative integer lesser than 100, inserts the nth parenthesized submatch string, provided the first argument was a RegExp object. |