[C++][MSVC] Cannot resolve this Linker error LNK2019, DirectX related

[The Teej]

Okay guys and gals, I am absolutely 100% stumped on this one. I genuinely cannot seem to resolve this one. I've been trying for 5 days, experimenting, googling, all to no avail. I usually like to solve my own coding problems and try for as long as I can to resolve it, but this time I need some outside advice!

Basically, I'm using DirectX for my input. I have a CInput class using dinput.h to grab keyboard inputs. My compiler is MSVC++ 2010.

CInput.h

// input.h: interface for the Cinput class.
//
//////////////////////////////////////////////////////////////////////
#if !defined(AFX_INPUT_H__9F947E83_2A3B_4B63_8675_83B41506943E__INCLUDED_)
#define AFX_INPUT_H__9F947E83_2A3B_4B63_8675_83B41506943E__INCLUDED_
#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000
#include <windows.h>
#define DIRECTINPUT_VERSION 0x0700
#include <dinput.h>

class CInput
{
private:
static CInput * _instance;
protected:
CInput(void);
public:
static CInput * Instance();
virtual ~CInput();
void GetInput();
bool GetIfKeyDown(int whichkey); //true as long as key still down
bool GetIfKeyDownEvent(int whichkey); //occurs only when key first pressed
};
#endif // !defined(AFX_INPUT_H__9F947E83_2A3B_4B63_8675_83B41506943E__INCLUDED_)
[/CODE]

CInput.cpp

[CODE]
// input.cpp: implementation of the Cinput class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Input.h"
#include <windows.h>
#include <OBJBASE.H>

extern HWND g_hWnd;
extern HINSTANCE hInst;
LPDIRECTINPUT lpdi; //pointer to direct input object
LPDIRECTINPUTDEVICE lpdikey; //the keyboard device
//storage for keyboard state
UCHAR keystate[256];
UCHAR oldkeystate[256];
bool keydown[256];
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
CInput::CInput()
{

if (DirectInputCreateA(hInst, DIRECTINPUT_VERSION, &lpdi, NULL)!=DI_OK)
{
// DirectInput not available; take appropriate action
}

//create keyboard device
if(lpdi->CreateDevice(GUID_SysKeyboard, &lpdikey, NULL)!=DI_OK)
{
//error
}
//set cooperation level
if(lpdikey->SetCooperativeLevel(g_hWnd, DISCL_BACKGROUND | DISCL_NONEXCLUSIVE)!=DI_OK)
{
//error
}
//set data format
if(lpdikey->SetDataFormat(&c_dfDIKeyboard)!=DI_OK)
{
//error
}
//acquire the keyboard device
if(lpdikey->Acquire()!=DI_OK)
{
//error
}

}
CInput::~CInput()
{
//unaquire keyboard
lpdikey->Unacquire();
lpdi->Release();
}
//this method refreshes the CInput class's data on which keys are currently down
//this data is stored in an array called keystate[ ]
void
CInput::GetInput()
{
//copy old keystate array
int i;
for (i=0;i<256;i++)
{
oldkeystate[i]=keystate[i];
}

if (lpdikey->GetDeviceState(256,keystate)!=DI_OK)
{
//error
}
//now check which keys are now down that weren't down last time
for (i=0;i<256;i++)
{
if ((keystate[i]>0)&&(oldkeystate[i]==0))
{
//key is now down and it wasn't before
keydown[i]=1;
}
else
{
keydown[i]=0;
}
}
}

//use this method with DirectX character constants
//which are defined in dinput.h such as DIK_SPACE
//relies on the GetInput( ) method being called first to
//update the data on which keys are currently down
//if this method doesn't seem to work then make sure you
//are calling GetInput( ) first!!!
bool
CInput::GetIfKeyDown(int whichkey)
{
if ((whichkey>256)|(whichkey<0)) return 0;
return (bool)(keystate[whichkey] & 0x80);
}
//method returns 1 or 0 depending on whether
//specified key has just been pressed
bool
CInput::GetIfKeyDownEvent(int whichkey)
{
if ((whichkey>256)|(whichkey<0)) return 0;
return (bool)(keydown[whichkey]);
}
CInput * CInput::Instance()
{
if (0==_instance)
{_instance=new CInput();
}
return _instance;
}
CInput * CInput::_instance=0;

[/CODE]

When I go to make a build, however, it compiles the code but throws up the linker error which I told you about. Here's my output from building:

[CODE]
1> Generating Code...
1>Input.obj : error LNK2019: unresolved external symbol _DirectInputCreateA@16 referenced in function "protected: __thiscall CInput::CInput(void)" (??0CInput@@IAE@XZ)
1>D:\Developer\ttSideScrollerWin32 - 2011 version\Debug\ttSideScrollerWin32.exe : fatal error LNK1120: 1 unresolved externals
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========
[/CODE]

From what I've read, LNK2019 usually gets thrown when something isn't being included in your project or hasn't been defined. However, the CInput Constructor has definitely been defined in my header, with both CInput.h and CInput.cpp included in my project. DirectX SDK is definitely installed, my Linker Input in my Project Properties includes dxguid.lib, dinput.lib and dinput8.lib. My VC++ Directories for Input and Libraries explicitly include DirectX SDK's folders for Input and Libraries. I've gone through everything I can think of, but everything seems to be in place. I presume it's some sort of compiler issue of some kind, and one that's probably beyond my expertise. However, I'm open to any suggestions. I'm returning to programming after a fair few months of inactivity and so I'm a little rusty, which probably hasn't helped me solve this issue.

So, please Neowin, help me!!!

[The Teej]

So.... yeah. I'm the world's biggest school-boy-erroring jackass.

Turns out, one small little thing I did right at the very beginning, which was re-naming dinput8.lib to dinput.lib in the very ignorant assumption would fix things, I forgot I did after I explored other avenues. Turns out, my code is pretty old now and was relying on an old version of DirectX SDK which used dinput.lib - which any DX programmer knows is pretty different to dinput8.lib (and both of which are pretty deprecated now anyway). A silly error made because I was rusty at coding. Installed a legacy version of DX which had dinput.lib, linked to that and it all compiles - thankfully. Of course, what I need to do now is re-write my Input class using a newer input library - anybody got any suggestions for input libraries in games? Just KB/M suppport is necessary but game controller support would be nice too!

[Andre S. Veteran]

XInput for controller + Win32 messages for mouse and keyboard (or whatever the format used by your windowing toolkit) is pretty much the way to go today. DirectInput was deprecated a long time ago.