C＃强制子类实现静态方法

Question

我目前正在建立一个类库来处理单位度量，我想将工厂模式与静态方法一起使用来创建长度或面积等等。

要保持方法的一致性，我想创建一个接口或超类。有没有可能强制子类实现静态方法的方法？

（Offtopic：是否也可以强制子类来重载运算符？）

例如：

public class Length
    {...


    public static Length Create(double value, string unitCode)
        {
            var length = new Length();

            switch (unitCode)
            {
                case "Mm":
                    length.Megameters = value;
                    break;
                case "Km":
                case "km":
                    length.Kilometers = value;
                    break;
                case "hm":
                    length.Hectometers = value;
                    break;
                case "dam":
                    length.Decameters = value;
                    break;
                case "m":
                    length.Meters = value;
                    break;
                case "dm":
                    length.Decimeters = value;
                    break;
                case "cm":
                    length.Centimeters = value;
                    break;
                case "mm":
                    length.Millimeters = value;
                    break;
                case "µm":
                    length.Micrometers = value;
                    break;
                case "pm":
                    length.Picometers = value;
                    break;
                case "in":
                    length.Inches = value;
                    break;
                case "ft":
                    length.Feet = value;
                    break;
                case "yd":
                    length.Yards = value;
                    break;
                case "mi":
                    length.Miles = value;
                    break;
                case "smi":
                    length.ScandinavianMiles = value;
                    break;
                case "ly":
                    length.LightYears = value;
                    break;
                case "NM":
                    length.NauticalMiles = value;
                    break;
                case "ftm":
                    length.Fathoms = value;
                    break;
                case "fur":
                    length.Furlongs = value;
                    break;
                case "ua":
                    length.AstronomicalUnits = value;
                    break;
                case "pc":
                    length.Parsecs = value;
                    break;
                default:
                    throw new ArgumentException("Not a valid unit given.", nameof(unitCode));
            }
            return length;
        }
... }