采集获取,关于正则表达式的多条结果,只获取1条,
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表达式 获取结果 /
有个疑问。
只获取第一条。
或者只获取最后一条。
这正则怎么写?
获取第一条,很多人认为会 /
- .*
- (.*?) / 除开这种,还会有其他吗?
- (.*?)\s*/
匹配第一条
用preg_match 不就行了
最后一条可以用 / - (.*?)\s*/
规则里有多个(.*?)的,需要返回的做数组处理。
例如
/ - ^2013-(.*?)(.*?) /
回复讨论(解决方案)
匹配第一条
用preg_match 不就行了
最后一条可以用 /
这样的话,后边不需要启动贪婪模式 U 吗
同时也需要 preg_match_all 的?
你不是要获取一条吗,用preg_match 就可以了。
规则里有多个(.*?)的,需要返回的做数组处理。
这个有影响吗,举例说明看看。
preg_match_all 返回的是数组,你可以选择用哪一条结果
你不是要获取一条吗,用preg_match 就可以了。
规则里有多个(.*?)的,需要返回的做数组处理。
这个有影响吗,举例说明看看。
测试了。正如你所说的。返回做数组是没影响的。
preg_match_all 返回的是数组,你可以选择用哪一条结果
其实 preg_match_all 和preg_match 都一样。1个是匹配所有合适的。一个是匹配一条合适的。

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