a subclass uses the keyword base to invoke a particular subclass constructor : base « Class « C# / CSharp Tutorial

1. C# / CSharp Tutorial
2. Class
3. base

using System;

public class Class1 {
    public static void Main(string[] args) {
        SubClass sc1 = new SubClass();

        SubClass sc2 = new SubClass(1, 2);

    }
}

public class BaseClass {
    public BaseClass() {
        Console.WriteLine("Constructing BaseClass (default)");
    }
    public BaseClass(int i) {
        Console.WriteLine("Constructing BaseClass({0})", i);
    }
}

public class SubClass : BaseClass {
    public SubClass() {
        Console.WriteLine("Constructing SubClass (default)");
    }
    public SubClass(int i1, int i2)
        : base(i1) {
        Console.WriteLine("Constructing SubClass({0}, {1})",
                                                  i1, i2);
    }
}