Java RegEx：只需获取匹配器组的一部分
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Java RegEx: Just get a part of the matcher group
提问by Tobias
I have a regex in Java:
我在 Java 中有一个正则表达式：
Pattern pattern = Pattern.compile(<string>text</string><string>.+</string>);
Matcher matcher = pattern.matcher(ganzeDatei);
while (matcher.find()) {
String string = matcher.group();
...
This works fine, but the output is something like
这工作正常，但输出类似于
<string>text</string><string>Name</string>
<string>text</string><string>Name</string>
But I just want this: Name
但我只想要这个： Name
How can I do this?
我怎样才能做到这一点？
回答by Andrzej Doyle
Capture the text you want to return by wrapping it in parenthesis, so in this example your regex should become
通过将其括在括号中来捕获要返回的文本，因此在此示例中，您的正则表达式应变为
<string>text</string><string>(.+)</string>
Then you can access the text that matched between the parenthesis with
然后您可以访问括号之间匹配的文本
matcher.group(1)
The no-arg groupmethod you are calling, returns the entire portion of the input text that matches your pattern, whereas you want just a subsequence of that, which matches a capturing group (the parenthesis).
您正在调用的 no-arg group方法返回与您的模式匹配的输入文本的整个部分，而您只需要一个与捕获组（括号）匹配的子序列。
回答by Sean Patrick Floyd
Then do this:
然后这样做：
Pattern pattern = Pattern.compile(<string>text</string><string>(.+)</string>);
Matcher matcher = pattern.matcher(ganzeDatei);
while (matcher.find()) {
String string = matcher.group(1);
...
Reference:
参考：
- Java Tutorial: Regex
- Pattern JavaDoc: Capturing Groups
- Matcher JavaDoc: Matcher.group(n)
- Matcher JavaDoc: Matcher.group()
- Java 教程：正则表达式
- 模式 JavaDoc：捕获组
- 匹配器 JavaDoc：Matcher.group(n)
- 匹配器 JavaDoc：Matcher.group()
回答by Micha? Niklas
You must put text you want to obtain by group()into brackets. So use:
您必须将要获取的文本group()放入括号中。所以使用：
<string>(.+)</string>
