Question

我一直收到错误

错误：找不到符号案例1：System.out.println（myCar [0]）;

我正在尝试创建一个基于菜单的应用程序，该程序将为3个子类创建5个超读初始数据实例的数组。我希望这能够显示不同的车号，用户可以输入他们想要的车号。然后程序应显示该车内保存的信息。

我想输出我为此5个实例中的每一个设置的详细信息。

public class Test
{
    int CarNo;
    static Scanner keyboard=new Scanner (System.in);

    public static void main(String[] args)
    {
        Ford myFord = new Ford ("AA1B2DD", "A", 1.1, 2.1, 3.1, 43.4, 9, 10.2);
        Ford myFord1 = new Ford ("AA1B2DD", "B", 1.1, 2.1, 3.1, 43.4, 9, 10.2);
        BMW myBMW = new BMW ("AA1B2DD", "C", 1.1, 2.1, 3.1, 43.4, 5.0, 100);
        BMW myBMW1 = new BMW ("AA1B2DD", "D", 1.1, 2.1, 3.1, 43.4, 5.0, 100);
        Merc myMerc = new Marquee ("AA1B2DD", "E", 1.1, 2.1, 3.1, 43.4, 5.0, 9, "wood");

        Car[] myCar = new Car [5];
        myCar[0]=myFord;
        myCar[1]=myFord1;
        myCar[2]=myBMW;
        myCar[3]=myBMW1;
        myCar[4]=myMerc;

        displayMenu();
    }

    public static void displayMenu()
    {
        System.out.println("Please select Which type of Car\n\n");

        for (int count =0; count <5; count++)
        {
            System.out.println("Car option number"+ "[" + (count +1) + "]  ");
        }
        System.out.println("\nEnter The Car Number you want");
        int CarNo=keyboard.nextInt();
        System.out.print("\n");
        if (CarNo <1 || CarNo >5)
        {
            System.out.println("Please enter a vaild Car nummber");
        }
        else
        {
            switch(CarNo)
            {
                case 1: System.out.println(myCar[0]);
                        break;
                case 2: System.out.println(myCar[0]);
                        break;
                case 3: System.out.println(myCar[0]);
                        break;
                case 4: System.out.println(myCar[0]);
                        break;
                case 5: System.out.println(myCar[0]);
                        break;
            }
        }
    }
}

Answer 1

require(ggplot2) te = structure(list(lat = c(33.7399, 32.8571, 50.2214, 36.96263, 33.5835, 33.54557, 47.76147, 48, 59.40289, 35.93411, 32.87962, 38.3241, 50.03844, 37.44, 50.07774, 50.26668, 36.5944), lng = c(-118.37608, -117.25746, -5.3865, -122.00809, -117.86159, -117.79805, -124.45055, -126, -146.35157, -122.931472, -117.25285, -123.07331, -5.26339, 25.4, -5.709894, -3.86828, -121.96201)), .Names = c("lat", "lng" ), class = "data.frame", row.names = c(NA, -17L)) all_states = map_data("world") # world version: wp = ggplot() + geom_polygon(data = all_states, aes(x = long, y = lat, group = group), colour = "gray", fill = "gray") + coord_cartesian(ylim = c(0, 80), xlim = c(-155, 45)) + geom_point(data = te, aes(x = lng, y = lat), color = "blue", size = 5,alpha = 0.6) print(wp) #states plot sp = ggplot() + geom_polygon(data = all_states, aes(x = long, y = lat, group = group), colour = "gray", fill = "gray") + coord_cartesian(ylim = c(30, 52), xlim = c(-128, -114)) + geom_point(data = te, aes(x = lng, y = lat), color = "blue", size = 5, alpha = 0.6) print(sp)方法中看不到myCar变量。尝试将其作为参数传递：

displayMenu()

此外，@ ryekayo的建议将为您提供准确的结果。

还要确保public static void displayMenu(Car[] myCar)类具有Car方法才能打印。

使用数组和case语句显示数据

1 个答案: