取字串中間的值，每個程式語言必然會遇到。Java 的解法：
If you have just a pair of brackets ( [] ) in your string, you can use indexOf():
String str = "ABC[ This is the text to be extracted ]";
String result = str.substring(str.indexOf("[") + 1, str.indexOf("]"));import java.util.Date; import org.apache.commons.lang.StringUtils; public class Main { public static void main(String[] args) { String helloHtml = "<html>" + "<head>" + " <title>Hello World from Java</title>" + "<body>" + "Hello, today is: " + new Date() + "</body>" + "</html>"; String title = StringUtils.substringBetween(helloHtml, "<title>", "</title>"); String content = StringUtils.substringBetween(helloHtml, "<body>", "</body>"); System.out.println("title = " + title); System.out.println("content = " + content); } }
String str = "ZZZZL <%= dsn %> AFFF <%= AFG %>";
Pattern pattern = Pattern.compile("<%=(.*?)%>");
String[] result = pattern.split(str);
System.out.println(Arrays.toString(result));it return
[ZZZZL , AFFF ]But my expectation is:
[ dsn , AFG ]
Your pattern is fine. But you shouldn’t be split()ting it away, you should find() it. Following code gives the output you are looking for:
String str = "ZZZZL <%= dsn %> AFFF <%= AFG %>";
Pattern pattern = Pattern.compile("<%=(.*?)%>");
Matcher matcher = pattern.matcher(str);
while (matcher.find()) {
System.out.println(matcher.group(1));
}這個 sample 滿好的，需要 import 到 2 個 Class，
java.util.regex.Pattern
java.util.regex.Matcher
需要 debug 的話，可以 output matcher.group(0) ，差異在包在括號外面的常數，要不要一起顯示， (1) 是只取出括號裡的變數，(0) 是包含外面常數。