C# 4.0 - How to Handle Optional String Parameters

Question

This code is not valid:

private void Foo(string optionalString = string.Empty)
{
   // do foo.
}

But this code is:

private void Foo(string optionalString = "")
{
   // do foo.
}

Why? Because string.Empty is a readonly field, not a constant, and defaults for optional parameters must be a compile-time constant.

So, onto my question... (well, concern)

This is what i've had to do:

private const string emptyString = "";

private void Foo(string optionalString = emptyString)
{
   // do foo.
   if (!string.IsNullOrEmpty(optionalString))
      // etc
}

How do you guys handle optional string parameters?

Why can they not make String.Empty a compile-time constant?

Answer 1

Ummm... what's wrong with string optionalParm = "" again? Why is that bad? Do you really think you need a symbolic constant for an empty string in this case? How about this then?

const int Zero = 0;

void SomeMethod(int optional = Zero) { }

Does that seem at all silly to you?