How to read Import Directory Table in C

I'm trying to build a PE viewer in C++ and it seems to crash if i try to output the names of the libraries in the Import Directory Table. It seems that I am not getting the correct pointers for the DLLs that are used by the program.

HANDLE handle = CreateFile("messagebox.exe",GENERIC_READ,0,0,OPEN_EXISTING,
                              FILE_ATTRIBUTE_NORMAL,0);
DWORD size = GetFileSize(handle,NULL);
PVOID virtualpointer = VirtualAlloc(NULL,size,MEM_COMMIT,PAGE_READWRITE);
state = ReadFile(handle,virtualpointer,size,&byteread,NULL);
CloseHandle(handle);
PIMAGE_NT_HEADERS ntheaders = PIMAGE_NT_HEADERS(PCHAR(vpointer) + 
                                     PIMAGE_DOS_HEADER(vpointer)->e_lfanew);
handle = GetCurrentProcess();
DWORD EntryAddr = ntheaders->OptionalHeader.ImageBase + 
                       ntheaders->OptionalHeader.AddressOfEntryPoint;

DWORD importdir = 
       (DWORD) &(ntheaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT]);

DWORD va = (DWORD)(ntheaders->OptionalHeader.ImageBase) + 
                     ((PIMAGE_DATA_DIRECTORY)dwValueB)->VirtualAddress;
LPSTR libname[128];
int i =0;
while(((PIMAGE_IMPORT_DESCRIPTOR)dwValueC)->Name)
{
       // get DLL name
       libname[i] = (LPSTR)(nt->OptionalHeader.ImageBase + 
                         ((PIMAGE_IMPORT_DESCRIPTOR)dwValueC)->Name);
       i++;
}