One of Web Biscuit's long-term secret projects is the This can be done in a RAII class. RAII stands for Resource Acquisition is Initialization, not the snappiest acronym in the whole wide world and not that self explanatory. Basically, we use the guarantee that creating an object always calls a constructor and eventually, a destructor. Played smartly, these two opposing calls can give us automatic Open/Close functionality. Here's our class: class CMidiOut
{
public:
CMidiOut() {}
~CMidiOut() {}
private:
HMIDIOUT m_hMidiOutHandle;
};
We could add class CMidiOut
{
public:
CMidiOut() :
m_hMidiOutHandle(nullptr)
{
midiOutOpen(
&m_hMidiOutHandle, // Handle
MIDI_MAPPER, // Default device
NULL, // No callback
NULL, // No callback parameters
CALLBACK_NULL); // Flags
}
~CMidiOut()
{
if(m_hMidiOutHandle != nullptr)
{
midiOutClose(m_hMidiOutHandle);
m_hMidiOutHandle = nullptr;
}
}
private:
HMIDIOUT m_hMidiOutHandle;
};
This is very cute. For a full solution, you'll want an accessor to your handle, and you'll need to prevent or handle copying of your class. These are all exciting subjects we can discuss next time.
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Lost your password?
