Question

我想在while循环中进行切换，在每个switch语句中断while循环停止并请求输入如F，R，C，Q。下面的语句有效，但语句不会中断。请帮忙

public static void main(String[] args) throws IOException {

    // start both with 1 point
    int goodTotal = 50;
    int monTotal = 50;

    // input switch statement

    while (goodTotal > 0 && monTotal > 0) {

        System.out.print("Type a letter: ");
        System.out.println("\n");
        System.out.print("F: Go out and Fight ");
        System.out.println("\n");
        System.out.print("R: Rest ");
        System.out.println("\n");
        System.out.print("C: Check Stats ");
        System.out.println("\n");
        System.out.print("Q: Quit ");
        int input = System.in.read();

        System.out.println("You typed: " + (char) input);

        switch (input) {
        case 'f':
            System.out.println("Continue the game");
            break;
        case 'r':
            System.out.println("Players should rest");
            break;
        case 'c':
            System.out.println("Checking the status of the game");
            System.out.print("Goodman has " + goodTotal + " points and Monster has " + monTotal + " points");
            System.out.println("\n");
            break;
        case 'q':
            System.out.println("Game over");
            System.exit(input);
            break;
        default:
            System.out.println("Invalid selection");
            break;
        }

        // Set value of minimum and maximum damage
        int minDmg = 2;
        int maxDmg = 15;

        // Get random number;
        int damage = minDmg + Double.valueOf(Math.random() * (maxDmg - minDmg)).intValue();
        int damage2 = minDmg + Double.valueOf(Math.random() * (maxDmg - minDmg)).intValue();

        // remove value of damage from started value to get total value remaining
        goodTotal = goodTotal - damage;
        monTotal = monTotal - damage2;

        // print message if still in the game
        if (goodTotal > 0) {
            System.out.println("Goodman has " + goodTotal + " points left. Not bad, Man! ");
        }

        // if Goodman survives round 2 print a message of encouragement
        if (goodTotal > 0 && count > 1 && count <= 2) {
            System.out.print("This is encouraging. Goodman has lasted past roundhh " + count + ". ");

            // print new message if Goodman passes round 3
        } else if (goodTotal > 0 && count == 3) {
            System.out.print("Goodman is as strong as Samson. He has lasted round " + count
                    + " and still looks strong.");
            System.out.print(" 10 hit points has been added to your total");
        }

        if (monTotal > 0) {
            System.out.println("Wait, Monster has a total of " + monTotal + " points and is still in the game");
        }

        // exit if have less than 0 point, and print game over. Congratulate the winner
        if (goodTotal < 0) {
            System.out.println("Goodman you are out of the game");
            System.out.println("The monster will take over the village. This is sad");
            System.out.println("Game Over!");
        } else if (monTotal < 0) {
            System.out.println("Goodman has been victorious");
            System.out.println("The monster is dead. The people live!!!!");
            System.out.println("Game Over!");
        }
        System.out.println("This is the end of round " + count + " ");
        System.out.println("\n");
        count = count + 1;

    }

}

Answer 1

在循环上使用标签：

loop: while (goodTotal > 0 && monTotal > 0) {
    // ...
    switch (input) {
        case 'f':
            // ...
            break loop;
        case 'r':
            // ...
            break loop;
        // ...
    }
    // ...
}

Answer 2

您应该使用labelled breaks.

尽管以不需要的方式重写代码可能更好，因为它们不是很容易阅读。

Answer 3

input的类型为 int ，但案例标签为字符文字（即f,r,c,q）。为什么不将input也设为char类型？

char input = System.in.read();

如何在java中的while循环中设置switch语句

3 个答案: