Question

我正在用java写一个刽子手游戏，我遇到了一个问题。我有一个方法，从数组中选择一个随机字并将其存储在一个变量中。现在在游戏运行的方法中，我将如何使用随机字变量？

public class Hangman {

public static Scanner qwe = new Scanner(in);

public static void word(){
    String words[]= {"Cat","dog"};

    int i = words.length;

    Random rng = new Random();
    int choice = rng.nextInt(words.length); //Varible storing random word

    gameStart();
}



public static void gameStart(){    //Asks user if they wish to start
    out.println("Welcome to my hangman game!");
    out.println("Would you like to begin?");
    String asd = qwe.nextLine().toLowerCase();
    if (asd.contains("y")){
        game();
    }
    else if (asd.contains("n")){
        exit(0);
    }
    else{
        out.println("Not a recognized answer");
        gameStart();
    }
}

public static void game(){
    out.println(choice);    //Trying to print out random word varible
}


public static void main(String[] args) {
    out.println("HangMan Game made by Ryan Hosford\n");
    gameStart();
}
}

Answer 1

您不能直接在其他method variables中使用methods，因为它们local method。

您可以将它们传递给该方法。或者将该方法设置为return所需的value并在您想要的地方打电话。

您无法使用word()方法。您可以返回value

public static int word(){
    String words[]= {"Cat","dog"};

    int i = words.length;

    Random rng = new Random();
    int choice = rng.nextInt(words.length); //Varible storing random word
    return choice;

}

然后，在game()方法

中使用上述方法

    public static void game(){    //Asks user if they wish to start
        int choice= word();   <-- call word that gives you choice
        // so now you have choice here. you can use it now.
         out.println(choice); 
}

Answer 2

在函数内声明变量时，它是该函数的本地变量。如果你想允许访问变量，你必须基本上声明它，使得该上下文中的每个函数都能够访问它。您可以使用嵌套调用将变量作为函数参数传递，也可以使用访问修饰符（例如static）声明变量。

BY通过将words[]= {"Cat","dog"}方法签名更改为gameStart()来使gameStart(String word)静态并使用所选单词调用gameStart（String word）：

public static String words[]= {"Cat","dog"};

public static int word(){
    int i = words.length;

    Random rng = new Random();
    int choice = rng.nextInt(words.length); //Varible storing random word

    gameStart(words[choice]);
}


public static void gameStart(String chosenWord){
//......... your code
 if (asd.contains("y")){
    game(chosenWord);
}
//....... your code

} 

 public static void game(String chosenWord)
 {
     System.out.println(chosenWord);
 }

或，添加静态字符串chosenWord，如下所示：

public static String chosenWord = ""; // using a static variable chosenWord
public static String words[]= {"Cat","dog"};
public static void word(){
        int i = words.length;

        Random rng = new Random();
        int choice = rng.nextInt(words.length); //Varible storing random word
        chosenWord = words[choice] ; // chosen word assigning
        gameStart();
    }

public static void game()
{
  System.out.println(chosenWord);
}

Answer 3

word()方法中的所有变量都是局部变量，它们的范围仅在它们声明的方法中。

为了延长选择的寿命，请创建一个字段（为方便起见静态）：

static String word;

public static void word(){
    ...
    word = words[rng.nextInt(words.length)];

然后word字段（变量）对另一种方法中的代码可见。

在不同的方法中使用变量？

3 个答案: