In the following code, call to Method2 receives the Value parameter as False, even though base class does not declare default value for the parameter at all, and derived class declares True as default.
It could be argued (as was done in similar example here: C# optional parameters on overridden methods) that the compiler uses base class's method declaration first (which is true, as this behavior can be changed by prefixing call to Method1 with this.), but in this case, the base does not declare default value at all.
Is there a rational explanation for this?
using System;
class Base
{
public virtual bool Method1(bool Value) { return true; }
public virtual bool Method2(bool Value) { return true; }
}
class Derived : Base
{
public override bool Method1(bool Value = true)
{
return Value;
}
public override bool Method2(bool Value = true)
{
return Method1();
}
}
class Program
{
static void Main(string[] args)
{
Derived a = new Derived();
Console.WriteLine("Call to Method1, expected: True, got: {0}", a.Method1());
Console.WriteLine("Call to Method2, expected: True, got: {0}", a.Method2());
}
}
Output:
Call to Method1, expected: True, got: True Call to Method2, expected: True, got: False
