变量超出范围

Question

我有一个错误，第 61 行指出变量 firstbattlerealactualhealth 超出了要使用的范围。我尝试了各种方法，但我似乎无法让它发挥作用。

如果您能告诉我哪里出了问题，以及我需要解决什么问题，我将不胜感激。

编辑：更改了哪个变量和行有问题，因为我无法计数或读取。

boolean firstbattle = true;
while (firstbattle) {
    int firstbattlehealth = HP;
    int firstbattleattack = Attack;
    int firstbattledefense = Defense;
    int firstbattleMP = MP;
    int firstbattleEXP = EXP;
    int firstbattlegold = Gold;

    int firstattack = (int) Math.ceil(Math.random() * 6);
    int firstdefense = (int) Math.ceil(Math.random() * 6);

    int firstenemyattack = (int) Math.ceil(Math.random() * 6);
    int firstenemydefense = (int) Math.ceil(Math.random() * 6);

    int firstenemyhealth = firstenemyfirsthealth;

    int firstenemynewhealth = firstenemyfirsthealth;

    int firstenemyhitpoints = (int) Math.ceil(Math.random() * 25);

    int firsthitpoints = 0;
    boolean firstkill = true;
    while (firstkill) {
        if (firstattack > firstenemydefense) {
            firsthitpoints = (int) Math.ceil(Math.random() * firstbattleattack);
            System.out.println();
            System.out.println("You did " + firsthitpoints + " damge to the Slime.");           
        }

        firstenemynewhealth = firstenemyhealth - firsthitpoints;

        if (firstenemynewhealth <= 0) {
           firstkill = false;
        }

        if (firstattack <= firstenemydefense) {
            System.out.println();
            System.out.println("Attack failed!");
        }
        int firstbattleactualhealth = firstbattlehealth;
        if (firstenemyattack > firstdefense) {
            int firstenemyhitpointattack = (int) Math.ceil(Math.random() * firstenemyhitpoints);
            int firstbattlerealactualhealth = firstbattleactualhealth - firstenemyhitpointattack;
            System.out.println();
            System.out.println("The enemy did " + firstenemyhitpointattack + " damage to you. You have " + firstbattlerealactualhealth + " health remaining.");
        }

        if (firstenemyattack <= firstdefense ) {
            System.out.println();
            System.out.println("Enemy attack missed!");
        }
    }

    int firstenemyactualhealth = firstenemynewhealth;
    if (firstenemyactualhealth <= 0){
        System.out.println();
        System.out.println("You won the battle!");

        HP = firstbattlerealactualhealth;
        EXP =  firstbattleEXP + 20;
        Gold = firstbattlegold + 20;
        System.out.println();
        System.out.println("You have " + HP + " health.");
        System.out.println("You have earned" + EXP + " experience.");
        System.out.println("You have earned" + Gold + " gold.");

        firstbattle = false;
    }
}

Answer 1

这可能是因为firstbattlerealactualhealth 是在if 子句中定义的。如果程序不执行if 块，firstbattlerealactualhealth 将不会被定义。你必须在你确定它会被执行的地方定义和初始化它。

归根结底，如果您在块内定义变量 ({})，则它应该只在该块内使用，而不能在其他任何地方使用。

提示：

不要命名任何变量first_sth。它后面必然跟着名称为second_sth 和third_sth 的变量，您将无法管理它们。您应该通过传递不同的参数将相同的逻辑用于其他战斗（不仅是史莱姆），这样您就可以编写 DRY（不要重复自己）代码。变量名也将更易读。