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Visual Studio 2008, MFC, CAsyncSocket
The programmer creates the overrides such as OnAccept(). Here is a fragment from elsewhere on this site:
void MyEchoSocket::OnAccept(int nErrorCode)
{
if(nErrorCode==0)
{
((CEchoServerDlg*)m_pDlg)->OnAccept();
}
CAsyncSocket::OnAccept(nErrorCode);
}
Note that the comment says and/or. The question is: Is there a need to have the call CAsyncSocket::OnAccept()? In the over-ride code can I just execute what I want done and forget that call to CAsyncSocket::OnAccept()?
Thanks for your time
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Here is the implementation of CAsyncSocket::OnAccept():
void CAsyncSocket::OnAccept(int )
{
}
As you see it doesn't count whether you call it or not but in my opinion its always better to upcall base class methods when you are not sure what to do and the upcall doesn't do any harmful thing to your code. In this case its unlikely that MS changes the implementation of such a core class but generally when you use others' classes as a baseclass its better not to build anything on assumptions. Imagine what happens if you refactor your socket code and you change the baseclass of your socket class from CAsyncSocket to another socket class of yours that does something meaningful in OnAccept()... So here I recommend the upcall as I think its a good practice.
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In general, you do want to call the base class method (be careful of when you call it, sometimes it's appropriate to do it before your code, sometimes you want to do it after your code).... in certain cases, it doesn't matter (it's an empty place holder) or you don't want the default behavior of the base class at all, in which case you don't call it at all.
If you don't call the base class method, be sure you know why you're not calling it because sometimes the methods will do things in the background that are important to the operation of the base class.
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This is a telemetry application where data arrives in a continuous stream. My application breaks that data out into named parameters and sends it to a display device. It generates at least two packets per millisecond and often ten or more.
As a result I will check to see if I can find any operations performed by the base class. When there are none time is saved by not making the call.
I do worry that they may be things done by that call that I do not have visibility into, hence the question.
Thank you for your time.
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So your real issue is how to process the data in the fastest way possible. When this is the issue it is usually best to avoid MFC classes and use the straight Win32 functions.
One of these days I'm going to think of a really clever signature.
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Good point. I started a new thread to ask that question.
Thanks for your time
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