Newbie asks: How does one implement this pattern in C#?

[Gomaw Beoyr]

Have you investigated nullable types in 2.0 yet?

Yes, you can use nullable types, but it then becomes really ugly
(I simplify here to one in and two out):

void F(double x, ref double? a, ref double? b) {
if (a != null) ...
if (b != null) ...
}

A caller that needs a but not b would have to do like this:

double? a;
double? b;
...
a = 0.0; // To make sure it's not null!
F(x, ref a, ref b);

And that sucks big time.

/Gomaw

 

[Jon Skeet [C# MVP]]

I thank you for your efforts, but all I wanted to know was if
there is any standard way in C# to do what you do in C when you
send the adderss of (i.e. pointer) to an out-variable as NULL,
to indicate that the value isn't needed by the caller.

I think what people have been trying to get you to do is to think about
the larger problem. It's really not a good idea to try to apply idioms
from one language or platform to another. Some of the worst Java code
I've seen is by C++ programmers trying to treat Java as if it were C++,
for instance. In this case, you're trying to write C# as if it were C.
It's not. You need different idioms - try to *think* in C# instead of
thinking in C and then translating those thoughts into C#.