Method Overloading with different return type [duplicate]

Question

I am want to dig in that whether it is an ambiguity or an extra feature that is provided:

 public class Foo   {      public int Bar(){        //code     }      public string Bar(int a){        //code     }  } 

Any one having any experience with this, overloading on return type with different parameters should be a bad practice, is it?

But if the overloading was done on the basis of return type then why this is not working for.

 public class Foo   {      public int Bar(int a){        //code     }      public string Bar(int a){        //code     }  } 

As it will be unable to decide which function to call 1st or second, if we call obj.Bar(); , it should end in error do any one have any idea about it why it allows first code snippet to run.

Answer 1

The C# specification (section 10.6) states that overloaded members may not differ by only return type and as per http://msdn.microsoft.com/en-us/library/ms229029.aspx

As per your question regarding creating parameters simply to support differing return types? I personally believe that is a terrible solution to the problem. Code maintenance will become difficult and unused parameters are a definite code smell. Does the method really need to be overloaded in that case? Or does it belong in that class? Should something else be created to convert from one return type to another? All things you should ask to derive a more idiomatic solution.

Answer 2

This is logically impossible. Consider the following call:

object o = Bar(42); 

or even

var o = Bar(42); 

How would the compiler know which method to call?

Edit: Now that I understand what you're actually asking, I think overloading by meaningless parameters is bad practice, and diminished readability, it is much preferable to distinguish by method name:

 string BarToStr()  {   }   int BarToInt()  {   }