Java 我不能在While循环中返回有什么原因吗？

我正在我的程序中处理一个方法，该方法必须返回值purchaseMethod。while循环需要运行，直到Q被输入控制台。我遇到的问题是，我无法在while循环中返回。这有什么办法吗？可能制作数组或for循环？如果return语句必须在while循环之外，那么如何将purchaseAmount的值保持为total

public static int getShoppingList(){
    Scanner input = new Scanner(System.in);
    int eight = 8;
    int hat = 32;
    int patch = 2;
    int sword = 20;
    int map = 100;
    int shirt = 150;
    int quanEight = 0;
    int quanHat = 0;
    int quanPatch = 0;
    int quanSword = 0;
    int quanMap = 0;
    int quanShirt = 0;
    int count = 0;

    System.out.println("Enter Item Code, ? or Q: ");
    String code = input.next();
    // Convert input into character
    char ch = code.charAt(0);
    // Convert string into uppercase
    ch = Character.toUpperCase(ch);
    // Calculate total 

    while (count != 0){
        int purchaseAmount = ( quanEight * eight) + ( quanHat * hat) + ( quanPatch * patch) + ( quanSword * sword) + ( quanShirt * shirt) + ( quanMap * map);
        if (ch == '?'){
            System.out.println("Valid Item codes are: 8 I H M S T.");
            System.out.println("Q to quit.");
        }
        else if (ch == '8'){
            quanEight ++; 

        }
        else if (ch == 'I'){
            quanHat++;
        }
        else if (ch == 'H'){
            quanPatch++;
        }    
        else if (ch == 'M'){
            quanMap++;
        }
        else if (ch == 'S'){
            quanSword++;
        }
        else if (ch == 'T'){
            quanShirt++;
        }     
        else if (ch == 'Q'){
            count++;
            System.out.println("Pirate Trading Post");
            System.out.println(quanEight + " Genuine Piece Of Eight\n " + quanHat + " Pirate Hat\n " + quanPatch + 
                " Eye Patch\n " + quanSword + " Sword\n " + quanMap + " Treasure Map\n " + quanShirt + " T-Shirt\n ");
            System.out.println("Total: " + purchaseAmount + " bits");
            return purchaseAmount;
        }
    }

}

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这是一个编译问题：

        int count = 0;

        while (count != 0){    // count **IS** 0, does not enter
            // your stuff
        }

        // no return

如果使用return命令打算将purchaseAmount返回给getShoppingList方法的调用方，我建议您将return移到方法的末尾，并在其while中加一个分隔符，而不是purchaseAmount。像这样：

while (count != 0){    
   // your stuff
   if (...) {
      // ...
   } else if (ch == 'Q'){
      // ...
      break;
   }
}
return purchaseAmount;

---

从while循环内返回是完全正确的-但是问题是，您也不会在while循环外返回-非void方法始终必须返回一个值。