C + + virtual functions and function pointers are used together

C + + virtual functions and function pointers are used together, which is a bit cumbersome to write.

A sample code is posted below for reference. (Need to support C++11 compilation)

1#include <stdio.h>2#include <list>3 using namespacestd;4 5 classVirtualwithcallback {6  Public:7     usingCallBack =void(Virtualwithcallback::*) (int);8 9  Public:Ten     Virtual voidTestcallback (intARG) =0; One  A     VirtualCallBack Getcallback ()Const=0; - }; -  the classVirtualWithCallBackSample1: PublicVirtualwithcallback { -  Public: - VirtualWithCallBackSample1 () { -CallBack = &Virtualwithcallback::testcallback; +     } -  +  Public: A     voidTestcallback (intArgOverride { atprintf"This is the virtual call 1:arg =%d\n", ARG); -     } -  -CallBack Getcallback ()Const Override { -         returnCallBack; -     } in  - Private: toCallBack CallBack =nullptr; + }; -  the classVirtualWithCallBackSample2: PublicVirtualwithcallback { *  Public: $ VirtualWithCallBackSample2 () {Panax NotoginsengCallBack = &Virtualwithcallback::testcallback; -     } the  +  Public: A     voidTestcallback (intArgOverride { theprintf"This is the virtual call 2:arg =%d\n", ARG); +     } -  $CallBack Getcallback ()Const Override { $         returnCallBack; -     } -  the Private: -CallBack CallBack =nullptr;Wuyi }; the  - classVirtualcaller { Wu  Public: -     voidPush (virtualwithcallback*callBack) { About Callbacklist.push_back (callBack); $     } -  -     voidrun () { -          for(Auto r:callbacklist) { A(R->* (R->getcallback ())) ( About); +         } the     } -  $ Private: theList<virtualwithcallback*>callbacklist; the }; the  the intMain () { - Virtualcaller caller; inCaller.push (NewVirtualWithCallBackSample1 ()); theCaller.push (NewVirtualWithCallBackSample2 ()); the Caller.run (); About     return 0; the}

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This article by Hassan Ya Qi Original, reproduced please indicate the source.

C + + virtual functions and function pointers are used together