1樓：小帥
div>testspan>span>.*?> : < ) 非貪婪匹配( < )
例如: /div>《術語叫貪婪匹配( <.*> : <
<
2樓：
* 號是乙個量詞
量詞後面加? 號表示非貪婪,也就是盡可能少的匹配* 可以是表示0 或者大於0個
所以 * 在貪婪的情況盡可能多的匹配
*? 就表示盡可能少的匹配
3樓：黃哥
請看"?" Matches 0 or 1 (greedy) of the preceding RE.
The special characters are:
"." Matches any character except a newline.
"^" Matches the start of the string.
"$" Matches the end of the string or just before the newline at
the end of the string.
"*" Matches 0 or more (greedy) repetitions of the preceding RE.
Greedy means that it will match as many repetitions as possible.
"+" Matches 1 or more (greedy) repetitions of the preceding RE.
"?" Matches 0 or 1 (greedy) of the preceding RE.
Non-greedy versions of the previous three special characters.
Matches from m to n repetitions of the preceding RE.
? Non-greedy version of the above.
"\\" Either escapes special characters or signals a special sequence.
Indicates a set of characters.
A "^" as the first character indicates a complementing set.
"|" A|B, creates an RE that will match either A or B.
Matches the RE inside the parentheses.
The contents can be retrieved or matched later in the string.
(?aiLmsux) Set the A, I, L, M, S, U, or X flag for the RE (see below).
Non-grouping version of regular parentheses.
(?P...) The substring matched by the group is accessible by name.
(?P=name) Matches the text matched earlier by the group named name.
A comment; ignored.
Matches if ... matches next, but doesn't consume the string.
Matches if ... doesn't match next.
(?<=...) Matches if preceded by ... (must be fixed length).
(?(?(id/name)yes|no) Matches yes pattern if the group with id/name matched,
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