Question

Now that we have extension methods in C#, Is there any point left in keeping overloads in implementation of any class for passing default values?
Why pollute the class implementation when overloads can be made extension methods?
Any advantage of overloads (for passing default values)?

I’m counting out the option of default parameters because it forces specific ordering of parameters (i.e. default ones can come in end) and the fact that default value gets compiled in client code and a service pack could possibly break because of that.

Answer 1

Now that we have extension methods in C#, Is there any point left in keeping overloads in implementation of any class for passing default values?

I would use optional arguments instead of extension methods to remove overloads.

Extension methods have quite a few disadvantages – they have less access to the private members, they have a discoverability issue (as they’re defined on a separate class), etc.

However, there are times when using overloaded methods and constructors are better than adding optional arguments – separate from the issues you already mentioned. This include:

• Working with languages which don’t understand optional arguments. C# and VB.Net are not the only .NET languages out there.
• Sometimes optional arguments just don’t cut it – for example, you often need a true default constructor, and optional arguments, while they look like it when hand writing code, behave very differently in the face of reflection/serialization/etc.