Best way to open files

[Dave Mill]

I have implemented a class which performs operations on some file
throughout different methods in the class.

I did this by making the ifstream a private class member and opening the
file in the constructor,

however someone told me this was bad practice to have the stream as a
class attribute.

what is the best way to do it?

 

[Donovan Rebbechi]

I have implemented a class which performs operations on some file
throughout different methods in the class.

I did this by making the ifstream a private class member and opening the
file in the constructor,

however someone told me this was bad practice to have the stream as a
class attribute.

Not sure why -- but here are two issues:
(1) you can't copy or assign. Not necessarily a problem, but depends on how
you're using it. You've got to think about whether the object you're modelling
can truly be "copied".
(2) stack space: sizeof(ifstream) is 280 on my compiler, so it's very waste
to create streams that you're not using

About (2): you can use pointer and dynamically allocate when you use it.
About (1): use a shared pointer if you want a working copy constructor and
assignment.

Cheers,