c++动态库中回调函数使用

dll 源文件 add.cpp

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 1 typedef int (*pfunc)(int, int);
 2 pfunc myadd;
 3 
 4 void __stdcall  add(pfunc add)
 5 {
 6     myadd = add;
 7 }
 8 
 9 int __stdcall  true_add(int x, int y)
10 {
11     return myadd(x, y);
12 }

def文件 add.def

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1 EXPORTS
2 
3 add            @1
4 true_add            @2    

生成库add.lib add.dll

调用dll的文件 callback.cpp

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 1 #include <iostream>
 2 #include <Windows.h>
 3 
 4 typedef int (*padd)(int, int);
 5 
 6 typedef void (CALLBACK *pfunc1)(padd);
 7 typedef int (CALLBACK *pfunc2)(int, int);
 8 
 9 int my_add(int a, int b)
10 {
11     return a + b ;
12 }
13 
14 
15 
16 int main(int argc, char* argv[])
17 {
18     HINSTANCE hDll = LoadLibrary("add.dll");
19     if (NULL == hDll)
20     {
21         std::cout << "load library add.dll failed" << std::endl;
22     }
23     pfunc1 pfAdd1 = (pfunc1)GetProcAddress(hDll, "add");
24     pfunc2 pfAdd2 = (pfunc2)GetProcAddress(hDll, "true_add");
25     pfAdd1(my_add);
26     int sum = pfAdd2(3, 5);
27     std::cout << sum << std::endl;
28 
29     return 0;
30 }

注：Vs编译dll时需要在Property/Linker/Input ->Module Definition File中加入add.def