Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
511 views
in Technique[技术] by (71.8m points)

c++ - array[byte] to HBITMAP or CBitmap

I have an array of bytes (which I read through a stream directly from a .bmp and then store as a BLOB in a database) which I want to display as icons in a CImageList. Therefore I want to somehow load my data into an HBITMAP or CBitmap. I have done it like this up to now, reading from a file:

hPic = (HBITMAP)LoadImage(NULL, strPath, IMAGE_BITMAP, dwWidth, dwHeight, LR_LOADFROMFILE | LR_VGACOLOR);
...
CBitmap bitmap;
bitmap.Attach(hPicRet);

But obviously, that only works for files, but not for byte-arrays. How can I get the same result, but reading from an array of byte?

Edit: Note that my array does not contain just the colour information, but rather the complete file as it is written on disk, including all headers and meta-data. It seems to me that discarding all that information is a bad idea.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

Assuming you have the information loaded into a BYTE array named bytes....

BITMAPFILEHEADER* bmfh;
bmfh = (BITMAPFILEHEADER*)bytes;

BITMAPINFOHEADER* bmih;
bmih = (BITMAPINFOHEADER*)(bytes + sizeof(BITMAPFILEHEADER));
BITMAPINFO* bmi;
bmi = (BITMAPINFO*)bmih;

void* bits;
bits = (void*)(bytes + bmfh->bfOffBits);

HDC hdc = ::GetDC(NULL);

HBITMAP hbmp = CreateDIBitmap(hdc, bmih, CBM_INIT, bits, bmi, DIB_RGB_COLORS) ;

::ReleaseDC(NULL, hdc);

It's a little messy and could use a hefty dose of error checking, but the basic idea is sound.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...