Go4Expert - Creating dll and including "winsock.dll" in the Network application

Hi,I was trying to create a simple dll file.Here is what I did .
First I created dll.h file which looked like this

Code:

#ifndef "dll.h"

#define "dll.h"

/*function prototype*/

void intsum(int);

#endif

then I saved it as dll.h .

Secondly I created a dllmain.cpp

#include<iostream>

#include "dll.h"

using namespace std;

class dll

{

public:

void intsum(int a)

{

a+=a;

cout<<a<<'\n';

}

};

I compiled it and I got a dll called by the of the project which was "Project1.dll"
from here
I include it in the application like this

Code:

#include<iostream>

#include "Project1.dll"

using namespace std;

int main()

{

int number;

printf("Enter Number :");

cin>>number; 

/*Here comes the function defined from the dll*/

function(number);

return 0;

}

But nothing worked,And one the Errors was
"Project1.dll" no such file or directory After this Error I tried to replace the second line with
#include "dll.h" still I got the Error said "function()" is undeclared (first use of this function) From there I didn't have anymore try and Everything stacked just like that.
This code above I was Just a trial Because I was developing a Network Application And I was supposed to include the "winsock.dll" in my application I don't know what to do right now.Any help please on how I going to get away with this. Also any tutorials on how to include the dll's in the application will be helpful.Thanks