Load image from Resource Files of a c++ CLR/CLI project - c++

Question

My project is a c++ CLR/CLI, I have some PNG images in my Resource Files and I want to change the BackgroundImage of a System::Windows::Forms::Button when the button is clicked, my code below:
#include <Windows.h>
#include "resource.h"
private: System::Void button1_Click(System::Object^ sender, System::EventArgs^ e) {
HBITMAP hBitMap = (HBITMAP) LoadImage(GetModuleHandle(NULL), MAKEINTRESOURCE(IDB_PNG2), IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
Bitmap^ bitMap = Bitmap::FromHbitmap((IntPtr) hBitMap);
DeleteObject(hBitMap);
button1->BackgroundImage = (System::Drawing::Image^) bitMap;
}
Here's my resource.h:
//{{NO_DEPENDENCIES}}
// Microsoft Visual C++ generated include file.
// Used by Disneyy.rc
//
#define IDB_PNG1 101
#define IDB_PNG2 102
#define IDB_PNG3 103
// Next default values for new objects
//
#ifdef APSTUDIO_INVOKED
#ifndef APSTUDIO_READONLY_SYMBOLS
#define _APS_NEXT_RESOURCE_VALUE 104
#define _APS_NEXT_COMMAND_VALUE 40001
#define _APS_NEXT_CONTROL_VALUE 1001
#define _APS_NEXT_SYMED_VALUE 101
#endif
#endif
When compiling I'm getting this error:
1>MyForm.obj : error LNK2028: unresolved token (0A000036) "extern "C" void * __stdcall LoadImageW(struct HINSTANCE__ *,wchar_t const *,unsigned int,int,int,unsigned int)" (?LoadImageW##$$J224YGPAXPAUHINSTANCE__##PB_WIHHI#Z) referenced in function "private: void __clrcall Disneyy::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click#MyForm#Disneyy##$$FA$AAMXP$AAVObject#System##P$AAVEventArgs#4##Z)
1>MyForm.obj : error LNK2028: unresolved token (0A00003F) "extern "C" int __stdcall DeleteObject(void *)" (?DeleteObject##$$J14YGHPAX#Z) referenced in function "private: void __clrcall Disneyy::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click#MyForm#Disneyy##$$FA$AAMXP$AAVObject#System##P$AAVEventArgs#4##Z)
1>MyForm.obj : error LNK2019: unresolved external symbol "extern "C" void * __stdcall LoadImageW(struct HINSTANCE__ *,wchar_t const *,unsigned int,int,int,unsigned int)" (?LoadImageW##$$J224YGPAXPAUHINSTANCE__##PB_WIHHI#Z) referenced in function "private: void __clrcall Disneyy::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click#MyForm#Disneyy##$$FA$AAMXP$AAVObject#System##P$AAVEventArgs#4##Z)
1>MyForm.obj : error LNK2019: unresolved external symbol "extern "C" int __stdcall DeleteObject(void *)" (?DeleteObject##$$J14YGHPAX#Z) referenced in function "private: void __clrcall Disneyy::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click#MyForm#Disneyy##$$FA$AAMXP$AAVObject#System##P$AAVEventArgs#4##Z)
EDIT:
Ok I fixed it by adding User32.lib to Additional Dependencies also specifying the Entry Point as main. However there's something wrong with this line:
HBITMAP hBitMap = (HBITMAP) LoadImage(GetModuleHandle(NULL), MAKEINTRESOURCE(IDB_PNG2), IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
Now I'm getting this error:
First-chance exception at 0x77130c3f in Disneyy.exe: 0xC0000005: Access violation reading location 0x00000066.
A first chance exception of type 'System.AccessViolationException' occurred in Disneyy.exe
An unhandled exception of type 'System.AccessViolationException' occurred in Disneyy.exe
Additional information: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
EDIT:
Once again I fixed it by changing IMAGE_BITMAP to BI_PNG, but now a new error comes up at line: Bitmap^ bitMap = Bitmap::FromHbitmap((IntPtr) hBitMap);
A first chance exception of type 'System.Runtime.InteropServices.ExternalException' occurred in System.Drawing.dll
An unhandled exception of type 'System.Runtime.InteropServices.ExternalException' occurred in System.Drawing.dll
Additional information: A generic error occurred in GDI+.

Answer 1

Finally after hours and hours of research I found an adapted solution which works just fine!
This solution is a combination of Giuseppe Pischedda's answer: https://www.codeproject.com/Articles/17996/Load-JPEG-images-from-DLL-with-LoadResource-in-Man
and Bordon's answer: https://social.msdn.microsoft.com/Forums/de-DE/c8dea6f9-0564-49d6-9782-117207031140/loadfromresource-fails-for-loading-png-files-from-resource?forum=vcmfcatl
adapted by me for PNG images:
public: System::Drawing::Image^ getImageFromRes(long resource_ID) {
// Function getImageFromRes
// A function for loading PNG images from resources in C++ CLR/CLI
// Copyright (C) Giuseppe Pischedda 2007 for most code
// and a little part of this code by Bordon and adapted by me for PNG images in C++ CLR/CLI.
//Load the resource module:
HMODULE hInst = NULL;
// Find the resource using the resource ID from file "resource.h"
HRSRC hResource = ::FindResource(hInst, MAKEINTRESOURCE(resource_ID), L"PNG");
if (!hResource) return nullptr;
// Load the resource and save the total size.
DWORD Size = SizeofResource(hInst, hResource);
HGLOBAL MemoryHandle = LoadResource(hInst, hResource);
if (MemoryHandle == NULL) return nullptr;
//Create a cli::array of byte with size = total size + 2
cli::array<BYTE>^ MemPtr = gcnew array<BYTE>(Size + 2);
//Cast from LPVOID to char *
char *lkr = (char *) (LockResource(MemoryHandle));
//Copy from unmanaged memory to managed array
System::Runtime::InteropServices::Marshal::Copy((IntPtr) lkr, MemPtr, 0, Size);
// Create a new MemoryStream with size = MemPtr
System::IO::MemoryStream^ stream = gcnew System::IO::MemoryStream(MemPtr);
//Write in the MemoryStream
stream->Write(MemPtr, 0, Size);
//Set the position for read the stream
stream->Position = 0;
//Free allocated resources
FreeLibrary(hInst);
//Create an Image abstract class pointer
System::Drawing::Image^ ptrPNG;
//Assign the stream to abstract class pointer
ptrPNG = System::Drawing::Image::FromStream(stream);
return ptrPNG;
}
Usage:
System::Drawing::Image^ image = getImageFromRes(IDB_PNG2);
if (image != nullptr) button1->BackgroundImage = image;