Question

Since making a type nullable essentially makes the variable “optional”, I’m wondering when it’s appropriate to use nullable types in method parameters in order to make them optional when using an overload could accomplish the same thing?

Answer 1

I wouldn’t – you’ll end up with a lot of null, null, null. In C# 4.0 you have optional parameters and named arguments; wait a few more months and consider using them. Until then, overloads, or pass it objects that represent the args:

SearchOptions options = new SearchOptions {
     Key = 123, Name = "abc"
     // but 27 other properties we **haven't** set
}
Search(options);