JAVA 开关，if then else 和带有字符串的布尔值

Question

我在让部分代码正常工作时遇到了一些麻烦。我对 java 还是有点陌生，能否提供一些指导和线索来指出我哪里出错了。

错误来自 if 语句。我觉得我知道他们为什么会犯错，因为 ||未定义，但我不确定如何修复它。我想让它做的是接受 L、R、F、B（左、右、前和后）的输入。小写输入并使用布尔值 "or".

接受一个或另一个

import java.util.Scanner;

public class 选择你的冒险 {

public static void main(String[]args) {
    Scanner input = new Scanner(System.in);             
    System.out.print("Choose a diection: ");
    String direction = input.nextLine().toLowerCase();
    System.out.printf(" %s and %s/n",getDirection (way),getYourChoice (found));

}

public static String getYourChoice (String found) {
    String result = "Unknown";
    switch (found)
    {
    case "l":
        result = " now we all know you can turn left unlike Zoolander";
        break;

    case "left":
        result = " now we all know you can turn left unlike Zoolander";
        break;

    case "r":
        result = " you fall down a hole never to be seen again... sad.";
        break;  

    case "right":
        result = " you fall down a hole never to be seen again... sad.";
        break;      

    case "f":
        result = " YOU ARE THE KWISATZ HADERACH!!";
        break;  

    case "forward":
        result = " YOU ARE THE KWISATZ HADERACH!!";
        break;

    case "b":
        result = " you are a scaredy cat but, you live to fight or runaway another day";
        break;

    case "back":
        result = " you are a scaredy cat but, you live to fight or runaway another day";
        break;
    }
    return result;
}

public static String getDirection(String way) {
    String result;
    if (way == "l" || "left") {
        System.out.print("Your character moves left");
    }

    else if (way == "r" || "right") {
        System.out.println("You character moves right");
    }

    else if (way == "f" || "forward") {
        System.out.println("Your character moves forward");
    }

    else if (way == "b" || "back") {
        System.out.println("Your character moves forward");
    }

    else {
        System.out.println(" You cant go that way ");
    }

    return result;
}

}

Answer 1

你所有的if陈述都是错误的。使用||或&&时，需要在||两边指定变量way：

if (way == "l" || way == "left") {
    System.out.print("Your character moves left");
}

JAVA 开关，if then else 和带有字符串的布尔值

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