java - 特殊形式的字符串输入验证

Question

我正在尝试排除员工编号 XXX-L，其中 x 是 0-9 范围内的数字，L 是 A-M 范围内的字母。我正在努力让这段代码发挥作用。但我无法输入有效的输入。

import java.util.Scanner;
import java.util.InputMismatchException;

public class ObjectOrinetPrograming
{
    public static void main( String [] args )
    {
        Scanner input = new Scanner (System.in);
        System.out.println("Please Enter elements: ");
        String employeenumber = input.nextLine();
        while (employeenumber.length() != 5)
        {
            System.out.println("invalid input; lenght, Try again:");
            employeenumber = input.nextLine();
        }


            while (employeenumber.charAt(4) != ('A'|'B'|'C'|'D'|'E'|'F'|'G'|'H'|'I'|'J'|'K'|'L'|'M'))
            {
                System.out.print("invalid input; charrecter match, try again:");
                employeenumber = input.nextLine();
            }


        while (employeenumber.charAt(0) == '-')
        {
            System.out.println("Invalid Input; form, try again:");
            employeenumber = input.nextLine();
        }
        }

}

Answer 1

您可以使用正则表达式来匹配输入的employeenumber。

public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.println("Please Enter elements: ");
    String employeenumber = input.nextLine();
    while (!employeenumber.matches("[0-9]{3}-[A-M]")) {
        System.out.println("invalid input; lenght, Try again:");
        employeenumber = input.nextLine();
    }

    System.out.println("Your employee id is " + employeenumber);

}