C++ – When using Win32 code in your modern C++ app, should you use proper casting

cvisual c++winapi

For example the following cast can be found littered throughout the MSDN documentation:

(LPTSTR)&lpMsgBuf

Should I bother converting that to:

static_cast<LPTSTR>(&lpMsgBuf);

Or should I just leave all the idiomatic C-esque Win32 portions as they are typically found in the docs, and save the more idiomatic C++ style/usage for the rest of my code?

Best Answer

New style casts were introduced for a reason: they're safer, more explanatory/self-commenting, easier to see, and easier to grep for.

So use them.

By more explanatory, we mean that you can't just cast to something, you have to say why you're casting (I'm casting in an inheritance hierarchy (dynamic_cast), my cast is implementation defined and possibly not portable (reinterpret_cast), I'm casting away constness (const_cast), etc.).

They're purposefully long and ugly so that the cast jumps out at the reader (and to discourage a programming style that employs too much casting).

They're safer because, e.g., you can't cast away constness without explicitly doing that.

Related Solutions

C++ – When should you use ‘friend’ in C++

Firstly (IMO) don't listen to people who say friend is not useful. It IS useful. In many situations you will have objects with data or functionality that are not intended to be publicly available. This is particularly true of large codebases with many authors who may only be superficially familiar with different areas.

There ARE alternatives to the friend specifier, but often they are cumbersome (cpp-level concrete classes/masked typedefs) or not foolproof (comments or function name conventions).

Onto the answer;

The friend specifier allows the designated class access to protected data or functionality within the class making the friend statement. For example in the below code anyone may ask a child for their name, but only the mother and the child may change the name.

You can take this simple example further by considering a more complex class such as a Window. Quite likely a Window will have many function/data elements that should not be publicly accessible, but ARE needed by a related class such as a WindowManager.

class Child
{
//Mother class members can access the private parts of class Child.
friend class Mother;

public:

  string name( void );

protected:

  void setName( string newName );
};

C++ – When should you use a class vs a struct in C++

The differences between a class and a struct in C++ is:

struct members and base classes/structs are public by default.
class members and base classes/struts are private by default.

Both classes and structs can have a mixture of public, protected and private members, can use inheritance and can have member functions.

I would recommend you:

use struct for plain-old-data structures without any class-like features;
use class when you make use of features such as private or protected members, non-default constructors and operators, etc.

Best Answer

Related Solutions

C++ – When should you use ‘friend’ in C++

C++ – When should you use a class vs a struct in C++

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