JOptionPane组件返回值显示问题求助：需将数字结果替换为指定字符（G/P/L/Y/N）

嘿，我看了你的代码，问题很明确——你直接把JOptionPane返回的整数结果输出了，没有把它们转换成你想要的字符（G/P/L和Y/N）。咱们一步步来解决：

错误点梳理 #

• 直接输出整数而非目标字符
  你在output8、output11、output12里直接拼接了answer1、answer3、answer4的整数值，但这些是JOptionPane的返回码：

  • 房间类型选择的0、1、2对应你定义的选项"G"、"P"、"L"
  • showConfirmDialog返回的0代表YES，1代表NO，你需要把它们转成Y和N

• String.format用法不规范
  你调用了String.format但还是用+直接拼接字符串，这完全浪费了format方法的格式化优势，应该用占位符（%s、%d等）来组织内容，代码更清晰也更易维护。

修正方案与完整代码 #

下面是修改后的代码，我标注了关键修改点：

import javax.swing.JOptionPane;

public class HotelReservation {
    public static void main(String[] args){
        JOptionPane.showMessageDialog(null, "Welcome to Easy Living Resort Hotel.\n" + 
            "----------------------------------------------------\n" + 
            " Room Type Daily Rate \n" + 
            "~~~~~~~~~~~~~ ~~~~~~~~~~\n" + 
            "G - Garden View Php 125.00\n" + 
            "P - Pool View Php 145.00\n" + 
            "L - Lake View Php 180.00\n");
        
        String[] options = new String[] {"G", "P", "L"};
        int answer1 = JOptionPane.showOptionDialog(null, 
            "G - Garden View\n" + "P - Pool View\n" + "L - Lake View\n", 
            "Please select room type:", 
            JOptionPane.DEFAULT_OPTION, JOptionPane.PLAIN_MESSAGE, null, options, options[0]);
        
        String answer2 = JOptionPane.showInputDialog(null, "Number of days staying: ");
        int answer3 = JOptionPane.showConfirmDialog(null, "Do you want use a Refrigerator for Php 2.50 each day.");
        int answer4 = JOptionPane.showConfirmDialog(null, "Do you want to avail an extra bed for Php 15.00.");

        // 关键修改1：将房间类型整数映射为G/P/L
        String roomType;
        switch(answer1) {
            case 0: roomType = "G"; break;
            case 1: roomType = "P"; break;
            case 2: roomType = "L"; break;
            default: roomType = "Unknown"; // 处理用户意外操作的情况
        }

        // 关键修改2：将确认对话框结果映射为Y/N，用JOptionPane常量更易读
        String fridgeOption = (answer3 == JOptionPane.YES_OPTION) ? "Y" : "N";
        String bedOption = (answer4 == JOptionPane.YES_OPTION) ? "Y" : "N";

        // 关键修改3：用String.format的占位符规范格式化输出
        String output1 = String.format("Welcome to Easy Living Resort Hotel.%n");
        String output2 = String.format("------------------------------------------------------------%n");
        String output3 = String.format(" Room Type Daily Rate %n");
        String output4 = String.format("~~~~~~~~~~~~~ ~~~~~~~~~~%n");
        String output5 = String.format("G - Garden View Php 125.00%n");
        String output6 = String.format("P - Pool View Php 145.00%n");
        String output7 = String.format("L - Lake View Php 180.00%n");
        String output8 = String.format("Please select room type: %s%n", roomType);
        String output9 = String.format("----------------------------------------------------------%n");
        String output10 = String.format("Number of days staying: %s%n", answer2);
        String output11 = String.format("Refrigerator in the room? (Y/N): %s%n", fridgeOption);
        String output12 = String.format("Extra bed in the room? (Y/N): %s%n", bedOption);
        String output13 = String.format("-----------------------------------------------------------%n");

        JOptionPane.showMessageDialog(null, 
            output1 + output2 + output3 + output4 + output5 + output6 + output7 + 
            output8 + output9 + output10 + output11 + output12 + output13);
    }
}

额外说明 #

• 我加入了default分支处理房间类型的意外情况，避免用户触发未知返回码时输出混乱；
• 使用JOptionPane.YES_OPTION而不是硬写0，让代码可读性更高，即使你忘记了返回码的具体数值，也能一眼看懂逻辑；
• 用%n代替\n作为换行符，让输出在不同操作系统上都能正常显示。

内容的提问来源于stack exchange，提问作者Syl