正则表达式仅第一次出现? [英] Regex to first occurrence only?

问题描述

假设我有以下字符串:

这是为了测试测试.这只是一个测试.结束.

this is a test for the sake of testing. this is only a test. The end.

我想选择this is a test和this is only a test.我到底需要做什么?

and I want to select this is a test and this is only a test. What in the world do I need to do?

我尝试的以下正则表达式产生了一个愚蠢的结果:

The following Regex I tried yields a goofy result:

this(.*)test(我也想捕获它之间的内容)

this(.*)test (I also wanted to capture what was between it)

returns 这是为了测试而测试.这只是一个测试

这似乎很容易让我忘记.

It seems like this is probably something easy I'm forgetting.

推荐答案

正则表达式是贪婪的，这意味着它会捕获尽可能多的属于 .* 匹配的字符.使其非贪婪尝试:

The regex is greedy meaning it will capture as many characters as it can which fall into the .* match. To make it non-greedy try:

this(.*?)test

? 修饰符将使其在匹配中捕获尽可能少的字符.

The ? modifier will make it capture as few characters as possible in the match.

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