Thread: How to refer an int type

I have one class A which has an "int" field b; I defined another int type variable c. When I make any changes to A.b, I want c changes accordingly such that c=A.b .

One can always add a line c=A.b whenever A.b changes. But is there any better way to do that such as the method used in C/C++ : we can let c be a reference of A.b? (eg.: c=&(A.b) in c++)

thanks

If I'm understanding correctly, I guess you could create an event that gets set in the mutator of class A's b field, subscribe to the event and change c accordingly?

Originally Posted by Salem

What's "frequent" ?
A million times a second?

If you write your method as an inline function, the compiler will likely optimise away any call overhead and reading the integer will be a single instruction anyway, without the need to resort to interface-busting trick accesses. This is commonly called "premature optimisation disease".

First rule is write clear simple code which does what you want.

well, by "frequent" I mean I will manipulate A in many methods of B now and in the future. Thus each time I write a method manipulating A, I have to add a line "c=A.b". If there is a way I can write just one line which links c to A.b, thus I can access c outside B in a read-only manner, and save some duplicated code lines ("c=A.b") and avoid some trouble in case of forgetting to add c=A.b.

That has nothing to do with the inline function to save some parameter stacking time.

Thanks.

Originally Posted by bling

in your example with List<int>, you can just write a property to return the value of .Count

i'm still not really clear what you're trying to do though. B sounds like a custom class. but can you explain in more detail with A and c's types are?

Currently I wrote a property "c" to return the value of .Count, but I have to add c= .Count everywhere .Count changes, right?

Originally Posted by cpjust

I don't know what language that is, but is isn't C++.

I don't know what was Mod doing? I posted it in C# section, and I am asking a C# question. Why move it to C++ section?

Originally Posted by Magos

What you're looking for is called a property. Syntactically it's like using a variable though technically it's still a function (method) call.

Code:

public class MyClass
{
  public int c
  {
    get
    {
      return A.c;
    }
  }

  private List<int> A;
}

And use it as such:

Code:

MyClass m = new MyClass();
int NrOfItemsInList = m.c;

Thanks! That's what I did last night! I was thinking too much and forgot the simplest way. I don't need a reference to A.c if I just use property like that.