22.dll调用技术

1.dll文件:

 #include <Windows.h>

 _declspec(dllexport) void message_hello()
 {
     MessageBoxA(, "hello", "hello", );
 }

 _declspec(dllexport) double add(double num1, double num2)
 {
     return num1 + num2;
 }

2.调用dll文件

#include <stdlib.h>
#include <Windows.h>

void main()
{
    HMODULE mod = LoadLibraryA("工具.dll");
    if (mod == NULL)
    {
        printf("load error\n");
        exit();
    }

    //获取函数地址
    void(*message_hello)() = (void(*)())GetProcAddress(mod, "message_hello");
    double(*add)(double, double) = (double(*)(double, double))GetProcAddress(mod, "add");

    //调用函数
    if (message_hello == NULL)
    {
        printf("find error\n");
    }
    else
    {
        message_hello();
    }

    if (add == NULL)
    {
        printf("find error\n");
    }
    else
    {
        printf("%f",add(,));
    }
    system("pause");
}

运行截图: