如何使用 IComparable 接口比较属于不同类的对象

Question

我正在尝试比较属于不同类的两个不同对象并使用IComparable 接口对它们进行排序。请在下面找到我的代码以及我可以改进的地方 我已经理解错误但不知道如何修复它。

public class Program : IComparable
{
    public static void Main(string[] args)
    {
        var newList = new List<Object>();
        newList.Add(new Program { carName = "mercedes benz", topSpeed = 160 });
        newList.Add(new SecondClass { carName = "BMW", topSpeed = 140 });
        newList.Sort();

        foreach (var list in newList)
        {
             Console.WriteLine(list.carName + " " + list.topSpeed);
             /* Getting an error on this line stating 'object' does not contain a definition for 'carName' and no extension method 'carName' accepting a first argument of type 'object' could be found (are you missing a using directive or an assembly reference?)*/
        }
    }

    public string carName { get; set; }
    public int topSpeed   { get; set; }

    public int CompareTo(Object obj)
    {
        Program classObject = (Program)obj;

        if (this.topSpeed > classObject.topSpeed)
            return 1;
        else if (this.topSpeed == classObject.topSpeed)
             return 0;
        else return -1;
    }
}

public class SecondClass
{
    public string carName { get; set; }
    public int topSpeed   { get; set; }
}

/* Edit: implemented abstract class however I am getting this "Unhandled Exception Message": System.InvalidCastException: Unable to cast object of type 'CSharpbasics.SecondClass' to type 'CSharpbasics.Program'.*/

public class SecondClass : Car { }

public abstract class Car : IComparable
{
    public string carName { get; set; }
    public int topSpeed   { get; set; }

    public int CompareTo(Object obj)
    {
        Program classObject = (Program)obj;

        if (this.topSpeed > classObject.topSpeed)
            return 1;
        else if (this.topSpeed == classObject.topSpeed)
             return 0;
        else return -1;
    }
}

public class Program : Car
{
    static void Main(string[] args)
    {
        var newList = new List<Car>();
        newList.Add(new Program { carName = "Wagon R", topSpeed = 160 });
        newList.Add(new SecondClass { carName = "Swift", topSpeed = 140 });

        newList.Sort();

        foreach (var list in newList) 
            Console.WriteLine($"{list.carName} {list.topSpeed});
    }
}

Answer 1

您应该创建一个抽象类 Car，这两个类都继承自该类，并实现了 CompareTo 函数。父类不一定是抽象的，但在这种情况下我认为它会更合适。