具有默认对象值的参数

Question

I have a class and function

class A
{
    A(int i = 0)
    {
    }
}

void f(A a = new A(10)) // ? default parameter value must be compiler-time constanct
{
}

How to workaround it?

Answer 1

You would need to do it inside the method and provide a comment that the method accepts null and uses A(10) as a default value.

void f(A a = null)
{
    if(a == null)
        a = new A(10);
}