正则表达式在完整的 XML 字符串或普通字符串中抓取验证 email 地址

Question

Need to grab string text of email value in big XML/normal string.

Been working with Regex for it and as of now below Regex is working correctly for normal String Regex: ^[\\w;#$%&amp?'*+/=?`{|}~^-]+(:.\\;[\\w?#$%&amp?'*+/=:`{|}~^-]+)*@(.,[a-zA-Z0-9-]+\\.)+[a-zA-Z]{1,6}$

Text: paris@france.c

but in case when above text is enclosed in XML tag it fails to return. <email>paris@france.c</email>

I am trying to amend some change to this regex so that it will work for both of the scenarios

Answer 1

You have put ^ at the beginning which means the "Start of the string", and $ at the end which means the "End of the string". Now, look at your string:

<email>paris@france.c</email>

Do you think, it starts and ends with an email address?

I have removed them and also escaped the - in your regex. Here you can check the following auto-generated Java code with the updated regex.

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Example {
    public static void main(String[] args) {
        final String regex = "[\\w!#$%&'*+/=?`\\{|\\}~^\\-]+(?:\\\\.[\\w!#$%&'*+/=?`\\{|\\}~^\\-]+)*@(?:[a-zA-Z0-9-]+\\.)+[a-zA-Z]{1,6}";
        final String string = "paris@france.c\n"
     + "<email>paris@france.c</email>";
        
        final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
        final Matcher matcher = pattern.matcher(string);
        
        while (matcher.find()) {
            System.out.println("Full match: " + matcher.group(0));
            
            for (int i = 1; i <= matcher.groupCount(); i++) {
                System.out.println("Group " + i + ": " + matcher.group(i));
            }
        }
    }
}

Output :

Full match: paris@france.c
Full match: paris@france.c