Java 作业格式化

Question

所以我正在参加 Java 入门类(class)，到目前为止我很享受它。我有一个我正在从事的类(class)的项目，该项目应该使用 Java 对话框来请求用户输入来为视频游戏创建一个角色，并且为角色生成生命值和货币。

我已经完成了所有工作，除了生成字符健康状况时，它应该停在小数点后两位，但无论我如何调整我的 DecimalFormat 代码，我都无法得到它停在那里。

这是我的代码:

// This imports the GUI
import javax.swing.JOptionPane;
import java.text.*;

// This is the class declaration
public class CharacterGen
{
    public static void main(String[] args)
    {
        // These are variable declarations
        final double BASE_CURRENCY = 10.55;
        final int BASE_HEALTH = 50;
        int minHealthBonus = 1;
        int maxHealthbonus = 5;

        // This string dictates what is displayed
        // in the input box title, the dialog box,
        // and the type of dialog box
        String charName;
        charName = JOptionPane.showInputDialog(null,
            "Enter your character's name", 
            "Welcome to Legendary Epics!",
            JOptionPane.QUESTION_MESSAGE);

        int startingHealth = 50 + (int) (Math.random() * 5);
        double startingCurrency = 10.55 - (double) (Math.random() * 1);
        DecimalFormat df = new DecimalFormat("#.##");
        System.out.printf("%.2s", startingCurrency);

        JOptionPane.showMessageDialog(null,
            "Your name is " + charName
                + " your starting health is " + startingHealth
                + " your starting currency is " + startingCurrency,
            "Your character stats",
            JOptionPane.INFORMATION_MESSAGE);
    }
}

如果你们能看一下，我们将不胜感激!

Answer 1

您只是连接了一个 double 值，而没有将其格式化为字符串。尝试如下方法 String.format():

JOptionPane.showMessageDialog(null, "Your name is " + charName + " your starting health is " + startingHealth +
" your starting currency is " + String.format("%.2f", startingCurrency),
                                    "Your character stats",
                                    JOptionPane.INFORMATION_MESSAGE);