Question

我只想验证参数是否仅由字母数字字符组成。我已经尝试过了，但它的行为并不像我喜欢的那样：

import java.util.Scanner;
import java.util.Random;
import java.lang.Math;
public class game
{   
 public static void main(String [] args){
   System.out.print("Number of players? ");
   Scanner kb = new Scanner(System.in);
   int numplayers = kb.nextInt();
   String [] playersArray = new String[numplayers];
   int guessesArray[] = new int [numplayers];
   int currscoresArray[] = new int [numplayers];
   int addscoresArray[] = new int [numplayers];
   int finalscoresArray [] = new int [numplayers];
   populateArray(playersArray);
   makeGuess(guessesArray);
}

public static void populateArray( String[] x){
   Scanner kb = new Scanner(System.in);
    for (int i = 0; i<x.length ; i++){
        System.out.print("Enter Player "+(i+1)+": ");
        x[i]=kb.nextLine();  
   }
}

public static void displayMenu(){
    int choice=0;
    Scanner kb = new Scanner(System.in);
    String[] args = {};
    while(true){
        System.out.println("Menu ");
        System.out.println("1. Make Guess");
        System.out.println("2. List Winner");
        System.out.println("0. Exit");
        System.out.print("Enter choice: ");
        choice = kb.nextInt();
        if (choice==0){
            System.out.print("Do you want to play a new game? Y/N: ");
            String ans = kb.next();
            if (ans.equals ("Y") || ans.equals ("y")){
                main(args);
            }
            break;
        } 
        switch (choice){
            case 1: makeGuess(); break;
            case 2: System.out.println("Option 2 selected"); break;
            default: System.out.println("Invalid choice");
        }
    }
     System.out.println("End of program");System.exit(0);
}

public static void makeGuess(){   
     Scanner kb = new Scanner(System.in);
    Random rand = new Random();
    int secret = rand.nextInt(10)+1;
    int guess = kb.nextInt();
    int diff = (int)(Math.abs(guess - secret));
    int score=0; 
    for (int i=0; i < x.length; i++){
       System.out.print("Enter your guess player "+(i+1)+": ");
       x[i]=kb.nextInt();
    } 
    if (diff == 0){
        score=score+10;
    }else if(diff<=10){
        score=score+5;
    }else if(diff<=20){
        score=score+2;
    }
    for (int i=0; i<x.length; i++){
        x[i]=score;

    }
}

返回：

something_with_underscores

我明显遗漏了一些明显的东西。有什么建议吗？

Answer 1

ValidatePattern支持正则表达式。如果模式匹配，则验证字符串。您没有验证字符串中的所有字符...只是一个！

更改正则表达式模式以匹配整个字符串将是一种方法。其他正则表达式也足够了。

[ValidatePattern('^[a-zA-Z0-9]+$')]$someVariableThatShouldOnlyContainAlphaNumerics = 'something_with_underscores'

请注意，设置默认值将绕过此验证，因为它未传递给该函数。

验证PowerShell参数是否为字母数字

1 个答案: