Question

我编写了一个Java程序来验证电子邮件地址，但该程序无法正常运行。例如：每当我们将输入设为“1”（不包括双引号）时，输出为“true”，但正确的输出必须为“false”。请帮忙，我哪里出错了。

/*This is a java program to verify email address*/

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

public class EmailVerifyer {

    public boolean isEmail(String email) {
        Pattern p = Pattern
            .compile("^[_a-zA-Z0-9-]+(.[_a-zA-Z0-9-]+)*@[a-zA-Z0-9-]+(.[a-zA-Z0-9-]+)*(.[a-zA-Z]{2,3})$");
        Matcher m = p.matcher(email);
        if (!m.matches())
            return true;
        else
            return false;

    }

    public static void main(String args[]) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("Enter an email which you would like to verify for correctness: ");
        String email = scanner.nextLine();
        EmailVerifyer emailVerifyer = new EmailVerifyer();
        System.out.println("Output: ");
        System.out.println(emailVerifyer.isEmail(email));
    }
}

Answer 1

替换

if(!m.matches())

与

if(m.matches())

Answer 2

替换

Pattern p = Pattern.compile("^[_a-zA-Z0-9-]+(.[_a-zA-Z0-9-]+)*@[a-zA-Z0-9-]+(.[a-zA-Z0-9-]+)*(.[a-zA-Z]{2,3})$");

与

Pattern p = Pattern.compile("^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$");

电子邮件验证程序出错

2 个答案: