Question

我编写了一个程序，在Deutch中随机选择一个动词，并要求您提供Perfekt表格。它会不断显示新的动词，直到你犯错。然后该程序会告诉您答案不正确，并告诉您已经获得了多少积分。程序还将点数写入test.txt文件，然后从中重新读取该数字。

这是我的程序的代码（它如上所述正常工作）。

import java.util.Random;    
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;
import java.io.*;

public class Verben{
  public static void main(String args[]){
    String glagol;
    String correct = "Correct!";
    String incorrect = "Incorrect!";
    int points = 0;
    boolean answer;

    File file = new File("test.txt");


    for(int i = 0; i <= points; i++){
        Random random = new Random();


        String verben[] = {"trinken", "lesen", "schwimmen", "sterben", "fahren"};
        String verbenAnswer[] = {"hat getrunken", "hat gelesen", 
               "hat geschwommen", "ist       gestorben", "ist gefahren"};
        glagol = verben[random.nextInt(verben.length)];
        System.out.println("Please enter correct form of verb!");
        System.out.println(glagol);
        String enter = Input.readLine();

        if(glagol.equals(verben[0]) && enter.equals(verbenAnswer[0])){
            answer = true;
            points += 1;
        }else if(glagol.equals(verben[1]) && enter.equals(verbenAnswer[1])){
            answer = true;
            points += 1;
        }else if(glagol.equals(verben[2]) && enter.equals(verbenAnswer[2])){
            answer = true;
            points += 1;
        }else if(glagol.equals(verben[3]) && enter.equals(verbenAnswer[3])){
            answer = true;
            points += 1;
        }else if(glagol.equals(verben[4]) && enter.equals(verbenAnswer[4])){
            answer = true;
            points += 1;
        }else{
            answer = false;
            points += 0;
        }

        if(answer == true){
            System.out.println(correct);
        }else{
            System.out.println(incorrect);
            System.out.println("You collected: " + points + "/" + (i+1));
        }   
    }

        try{
            PrintWriter output = new PrintWriter(file);
            output.println(points);
            output.close();
        }catch (FileNotFoundException ex){
            System.out.printf("ERROR: %s\n", ex);
        }
         try{
            Scanner input = new Scanner(file);
            int point = input.nextInt();
            System.out.printf("Points: %d\n", point);
        }catch(IOException ex){
            System.err.println("ERROR");
        }

    }
}

如何修改代码以永久存储test.txt文件中的所有尝试？我怎样才能确定历史最高分？每次运行程序后，我都想提醒我“什么是历史最高分”。

Answer 1

这样做的一种方法是......

在你的for循环之后，通过逐行读取文件来确定高分。为了简单起见，我们假设每行有一个分数。

    // determine the high score
    int highScore = 0;
    try {
        BufferedReader reader = new BufferedReader(new FileReader(file));
        String line = reader.readLine();
        while (line != null)                 // read the score file line by line
        {
            try {
                int score = Integer.parseInt(line.trim());   // parse each line as an int
                if (score > highScore)                       // and keep track of the largest
                { 
                    highScore = score; 
                }
            } catch (NumberFormatException e1) {
                // ignore invalid scores
                //System.err.println("ignoring invalid score: " + line);
            }
            line = reader.readLine();
        }
        reader.close();

    } catch (IOException ex) {
        System.err.println("ERROR reading scores from file");
    }

确定高分后，我们可以显示相应的信息。

    // display the high score
    if (points > highScore)
    {    
        System.out.println("You now have the new high score! The previous high score was " + highScore);
    } else if (points == highScore) {
        System.out.println("You tied the high score!");
    } else {
        System.out.println("The all time high score was " + highScore);
    }

最后，我们将当前分数附加到文件的末尾（在它自己的行上）。

    // append the last score to the end of the file
    try {
        BufferedWriter output = new BufferedWriter(new FileWriter(file, true));
        output.newLine();
        output.append("" + points);
        output.close();

    } catch (IOException ex1) {
        System.out.printf("ERROR writing score to file: %s\n", ex1);
    }
}

Answer 2

如果要在程序开头显示历史最高分，则需要在程序开头读取文件。将文本文件中的所有条目添加到ArrayList（或类似的东西）中，然后找到列表中最大的元素，显示它。（或者，如果您以后不需要其他分数，请在阅读文件时跟踪最大元素。）

此外，当您为文件写分数时，您需要确保将其添加到文件的末尾，而不是覆盖文件。

将游戏分数保存到文件并确定“高分”

2 个答案: