C++ calling a dll.
Post date: May 12, 2011 3:52:05 AM
Ok lets say we have a function we want to call in C++. We would normally do this:
/* declare the function */
int MyFunction(char*,int);
int main(void)
{
returnMyFunction("hello", 5);
}
/* our function */
int MyFunction(char*,int)
{
/* do something */
return 0;
}
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But in our case that same function is in a dll. Ok let's see how we do it.
Your dll is located on the C:\ drive for example and is named "MyDLL.dll". It
contains a function called "MyFunction". Create a function that calls the dll's function like so:
int CallMyDLL(void)
{
/* get handle to dll */
HINSTANCE hGetProcIDDLL = LoadLibrary("C:\\MyDLL.dll");
/* get pointer to the function in the dll*/
FARPROC lpfnGetProcessID = GetProcAddress(HMODULE (hGetProcIDDLL),"MyFunction");
/*
Define the Function in the DLL for reuse. This is just prototyping the dll's function.
A mock of it. Use "stdcall" for maximum compatibility.
*/
typedef int (__stdcall * pICFUNC)(char *, int);
pICFUNC MyFunction;
MyFunction = pICFUNC(lpfnGetProcessID);
/* The actual call to the function contained in the dll */
int intMyReturnVal = MyFunction("hello", 5);
/* Release the Dll */
FreeLibrary(hGetProcIDDLL);
/* The return val from the dll */
returnintMyReturnVal;
}
You can just copy and paste the above into your project and change the prototyping to match your dll's function.