Question

win32编程，非MFC，用图片地址来使图片控件显示图片

用win32编程，非MFC，就是用一个图片控件，要实现通过代码，用图片地址来使图片显示在控件上（为的是登录界面，用户可以选择一个头像）。。要怎么做，求大神回复

Answer 1

#define WIN32_LEAN_AND_MEAN             // 从 Windows 头中排除极少使用的资料
#include <windows.h>
#include <tchar.h>


/****************************************************************************
CDrawBitmap封装了一些画图片的函数。

调用如下：
	CDrawBitmap g_bmp1("D:\\My Documents\\My Pictures\\风景图片\\4244123431.bmp");
	g_bmp1.Draw(m_hWnd);
    
	CDrawBitmap g_bmp2("D:\\My Documents\\My Pictures\\风景图片\\plane.bmp");
	g_bmp2.DrawTransparent(m_hWnd);

	CDrawBitmap g_bmp3("D:\\My Documents\\My Pictures\\风景图片\\jzg2.bmp");
	g_bmp3.DrawTransparent(m_hWnd);

****************************************************************************/

//使用TransparentBlt需要添加 #pragma comment(lib,"msimg32.lib")
#pragma comment(lib,"msimg32.lib")

class CDrawBitmap
{
private:
	HBITMAP m_bitmap;
	int m_bitmap_cx;
	int m_bitmap_cy;
public:	
	CDrawBitmap()	{} 
	CDrawBitmap(TCHAR * PicturePath)	{	LoadPicture(PicturePath);	} 
	CDrawBitmap(WORD ResourceID)		{	LoadResource(ResourceID);	} 

	~CDrawBitmap()	{ ::DeleteObject(m_bitmap);}	

	bool LoadPicture(TCHAR * PicturePath)
	{
		m_bitmap=(HBITMAP)LoadImage(NULL,		//应用程序实例			
			PicturePath,					//路径
			IMAGE_BITMAP,				
			0,								//如果不置0,则此参数指定m_bitmap的宽(位图被拉伸)		
			0,								//如果不置0,则此参数指定m_bitmap的高(位图被拉伸)		
			LR_LOADFROMFILE|LR_CREATEDIBSECTION|LR_DEFAULTSIZE);
		
		if (!m_bitmap)
			return false;

		BITMAP bmp;   
        GetObject(m_bitmap,sizeof(BITMAP),(LPSTR)&bmp);  
		m_bitmap_cx=bmp.bmWidth;
		m_bitmap_cy=bmp.bmHeight;

		return true;
	}

	bool LoadResource(WORD ResourceID)
	{
		m_bitmap=LoadBitmap(GetModuleHandle(NULL),MAKEINTRESOURCE (ResourceID) );	

		if (!m_bitmap)
			return false;

		BITMAP bmp;   
        GetObject(m_bitmap,sizeof(BITMAP),(LPSTR)&bmp);  
		m_bitmap_cx=bmp.bmWidth;
		m_bitmap_cy=bmp.bmHeight;

		return true;
	}

	void Draw(HWND hWnd=NULL,int x=0,int y=0,int width=100,int height=100)
	{
		HDC hScrDC=GetDC(hWnd);								//创建屏幕DC
		Draw(hScrDC,x,y,width,height);
		::ReleaseDC(hWnd,hScrDC) ;							//释放屏幕DC
	}

	void Draw(HDC hScrDC,int x=0,int y=0,int width=100,int height=100)
	{
		HDC hMemDC=CreateCompatibleDC(hScrDC);				//创建内存DC
		::SelectObject(hMemDC,m_bitmap);						//把位图选进内存DC
		BitBlt(hScrDC,x,y,width,height,hMemDC,0,0,SRCCOPY);	//内存DC映射到屏幕DC
		::DeleteDC(hMemDC) ;								//删除内存DC
	}


	void DrawTransparent(HWND hWnd=NULL,int x=0,int y=0)
	{
		HDC hScrDC=GetDC(hWnd);								//创建屏幕DC
		DrawTransparent(hScrDC,x,y);
		::ReleaseDC(hWnd,hScrDC) ;							//释放屏幕DC
	}

	//不进行拉伸处理，如需要，请自行修改代码TransparentBlt中的参数
	//使用TransparentBlt需要添加 #pragma comment(lib,"msimg32.lib")
	void DrawTransparent(HDC hScrDC,int x=0,int y=0,UINT crTransparent=RGB(255,255,255))
	{
		HDC hMemDC=CreateCompatibleDC(hScrDC);				//创建内存DC
		::SelectObject(hMemDC,m_bitmap);						//把位图选进内存DC
		::TransparentBlt(hScrDC,x,y,m_bitmap_cx,m_bitmap_cy,hMemDC,0,0,m_bitmap_cx,m_bitmap_cy,crTransparent);
		::DeleteDC(hMemDC) ;								//删除内存DC
	}


	void DrawStretch(HWND hWnd=NULL,int x=0,int y=0,int width=100,int height=100)
	{
		HDC hScrDC=GetDC(hWnd);								//创建屏幕DC
		DrawStretch(hScrDC,x,y,width,height);
		::ReleaseDC(hWnd,hScrDC) ;							//释放屏幕DC
	}

	void DrawStretch(HDC hScrDC=NULL,int x=0,int y=0,int width=100,int height=100)
	{
		HDC hMemDC=CreateCompatibleDC(hScrDC);				//创建内存DC
		::SelectObject(hMemDC,m_bitmap);						//把位图选进内存DC
		SetStretchBltMode(hScrDC,COLORONCOLOR);		//一定要先调用这个
		StretchBlt(hScrDC,x,y,width,height,hMemDC,0,0,m_bitmap_cx,m_bitmap_cy,SRCCOPY);	//内存DC映射到屏幕DC
		::DeleteDC(hMemDC) ;								//删除内存DC
	}
};


void DrawBitmap(HBITMAP m_bitmap,HDC hScrDC,int x=0,int y=0,int width=100,int height=100)
{
	HDC hMemDC=CreateCompatibleDC(hScrDC);				//创建内存DC
	::SelectObject(hMemDC,m_bitmap);						//把位图选进内存DC
	BitBlt(hScrDC,x,y,width,height,hMemDC,0,0,SRCCOPY);	//内存DC映射到屏幕DC
	::DeleteDC(hMemDC) ;								//删除内存DC
}

void DrawBitmap(HBITMAP m_bitmap,HWND hWnd=NULL,int x=0,int y=0,int width=100,int height=100)
{
	HDC hScrDC=GetDC(hWnd);								//创建屏幕DC
	DrawBitmap(m_bitmap,hScrDC,x,y,width,height);
	::ReleaseDC(hWnd,hScrDC) ;							//释放屏幕DC
}




CDrawBitmap g_bmp1("E:\\pictures\\风景图片\\Sunset.bmp");



LRESULT CALLBACK WndProc(HWND hWnd,UINT message,WPARAM wParam,LPARAM lParam)
{
	switch(message)
	{
	case WM_PAINT:
		{
			PAINTSTRUCT ps;
			HDC hdc;
			hdc = ::BeginPaint(hWnd, &ps);

			g_bmp1.Draw(hdc,0,0,500,500);

			::EndPaint(hWnd, &ps);
		}
		break;

	case WM_CLOSE:
		PostQuitMessage(0);
		break;
	default:
		return DefWindowProc(hWnd,message,wParam,lParam);
	}
	return 0;
}


HWND CreateMainWnd(WNDPROC  lpfnWndProc);

int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int nCmdShow)
{ 
	//create window
	HWND MainWnd=CreateMainWnd(WndProc);
	if ( !MainWnd )
		return false; 

	MSG msg;
	while(GetMessage(&msg,NULL,0,0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}		
	return msg.wParam ;
}  



static
HWND CreateMainWnd(WNDPROC  lpfnWndProc)
{
	WNDCLASS wndcls;
	wndcls.cbClsExtra	 =	0;
	wndcls.cbWndExtra	 =	0;
	wndcls.lpszMenuName	 =	NULL;
	wndcls.hInstance	 =	NULL;
	wndcls.style		 =	CS_HREDRAW|CS_VREDRAW;
	wndcls.hCursor		 =	LoadCursor(NULL,IDC_ARROW);
	wndcls.lpszClassName =	_T("Demo_MainWnd");		
	wndcls.hbrBackground =	(HBRUSH)GetStockObject(WHITE_BRUSH);
	wndcls.hIcon		 =	LoadIcon(::GetModuleHandle(NULL),NULL);
	wndcls.lpfnWndProc	 =	lpfnWndProc;

	if (!RegisterClass(&wndcls))
		return NULL;

	HWND hWnd = CreateWindowEx( NULL  ,_T("Demo_MainWnd"),_T("Demo"),WS_OVERLAPPEDWINDOW,225,160,400,240,NULL,NULL,NULL,NULL) ;

	if (!hWnd)	
	{
		::MessageBox(NULL,TEXT("Can Not Create MainWnd"),_T("标题"),MB_OK);	
		return NULL;
	}

	ShowWindow(hWnd,SW_SHOWNORMAL);
	UpdateWindow(hWnd);

	return hWnd;
}

Answer 2

使用api LoadImage函数加载位图，之后显示在图片控件上面。