win7 的GetProAddress地址會變動，所以該程式碼不適用於win7

// 遠端執行緒注入_呼叫API.cpp : 定義控制檯應用程式的入口點。
//

#include "stdafx.h"
#include "windows.h"

typedef int (_stdcall * Type_MessageBoxA)(HWND hWnd,LPCSTR lpText,LPCSTR lpCaption,UINT uType);

typedef HMODULE (_stdcall * Type_LoadLibraryA)(LPCSTR lpLibFileName);

typedef FARPROC (_stdcall * Type_GetProcAddress) (HMODULE hModule, LPCSTR lpProcName);

typedef struct 
{
	DWORD Add_LoadLibraryA;
	DWORD Add_GetProcAddress;
	char DLLname[20];
	char APIname[20];
	char Param1[20];
} Param_Str;

DWORD GetFunAddress(PUCHAR lpFunStart)
{
	DWORD dwFunAddress;
	if (*lpFunStart==0xE9)
	{
		//在Debug版本里VC會做一個跳轉
		dwFunAddress = (DWORD)lpFunStart+*(DWORD *)(lpFunStart+1)+5;
	}
	else
	{
		dwFunAddress = (DWORD)lpFunStart;
	}
	return dwFunAddress;
}

__declspec (naked) VOID FunFirst(){_asm{nop}};//定義函式結束的位置

int _stdcall  romente_true(Param_Str *P_str)
{
	Type_LoadLibraryA p_LoadLibraryA;
	Type_GetProcAddress p_GetProcAddress;
	Type_MessageBoxA p_MessageBoxA;
	FARPROC Func_add;

	p_LoadLibraryA=(Type_LoadLibraryA)P_str->Add_LoadLibraryA;
	p_GetProcAddress=(Type_GetProcAddress)P_str->Add_GetProcAddress;
	
	Func_add=p_GetProcAddress(p_LoadLibraryA(P_str->DLLname),P_str->APIname);//獲取該函式的地址

	p_MessageBoxA =(Type_MessageBoxA)Func_add;
	p_MessageBoxA(NULL,P_str->Param1,P_str->Param1,MB_YESNO|MB_ICONQUESTION|MB_DEFBUTTON1|MB_SYSTEMMODAL); 
	return 0;
};

__declspec (naked) VOID FunEnd(){_asm{nop}};//定義函式結束的位置

bool InjectFunc()
{
	LPVOID ParamAddr;
	LPVOID FuncAddr;
	HANDLE hProcess;
	HWND hWnd;
	DWORD Pid;
	HANDLE hThread;
	Param_Str params;
	DWORD ParamSize;

	//SIZE_T lpNumberOfBytes;
	DWORD FuncAddr_First,FuncAddr_End,FuncAddr_Size;
	//1 將函式寫入目標程式
	hWnd=FindWindowA(NULL,"計算器");
	GetWindowThreadProcessId(hWnd, &Pid)   ; 
	hProcess = OpenProcess(PROCESS_ALL_ACCESS, false, Pid);

	FuncAddr_First=GetFunAddress((PUCHAR)romente_true);
	FuncAddr_End=GetFunAddress((PUCHAR)FunEnd);
	FuncAddr_Size=FuncAddr_End-FuncAddr_First;

	FuncAddr = VirtualAllocEx(hProcess,  NULL, FuncAddr_Size, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
	WriteProcessMemory(hProcess,FuncAddr,(PVOID)FuncAddr_First, FuncAddr_Size, NULL);

	strcpy(params.APIname,"MessageBoxA");
	strcpy(params.DLLname,"user32.dll");
	strcpy(params.Param1,"asd");
	params.Add_LoadLibraryA= (DWORD)GetProcAddress( GetModuleHandleA("kernel32.dll"), "LoadLibraryA");
    params.Add_GetProcAddress= (DWORD)GetProcAddress( GetModuleHandleA("KernelBase.dll"), "GetProcAddress");//此處大問題，WIN7的GetProcAddress每個程序的基地址都不同

	ParamSize=sizeof(params);
	if (ParamSize)
	{
		ParamAddr = VirtualAllocEx(hProcess,NULL, ParamSize, MEM_COMMIT, PAGE_READWRITE);
		WriteProcessMemory(hProcess,  ParamAddr,  (LPCVOID)¶ms, ParamSize, NULL);
	}
	printf("0x%x\n",params.Add_GetProcAddress);
	romente_true(¶ms);
	
	hThread = CreateRemoteThread(hProcess, NULL, 0,(LPTHREAD_START_ROUTINE)FuncAddr, ParamAddr, 0, NULL);// 建立遠端執行緒    
	WaitForSingleObject(hThread, INFINITE) ;

	return true;
}

int _tmain(int argc, _TCHAR* argv[])
{
	InjectFunc();
	return 0;
}