C++ GDI+ loading an image from a file then deleting the file *before* unloading the image

Question

Simply what it says on the tin I'm loading a bitmap from a file using Bitmap::FromFile but afterwards I want to delete it from the disk.
The problem is, Bitmap::FromFile absolutely locks the file from any changes/deletion until the loaded image is unloaded

This is because I'm storing the bitmaps in a binary file, so I want to do it in this order:
1. extract the image from binary file
2. load the image
3. delete the file extracted in #1
(just some basic protection for my image resources, I just don't want them sitting in my program directory)

Bitmap::FromFile still locks the file from deletion even when cloning the loaded image from the file like in my attempt:

    Bitmap* tempbmp = Bitmap::FromFile(fileanddir.c_str(),false);
    Rect temprect( 0, 0, tempbmp->GetWidth(), tempbmp->GetHeight() );

    // make the image to be used as a clone to the temporary
    // bitmap to avoid file locking
    image_to_be_used = tempbmp->Clone(temprect, PixelFormatDontCare);

    // delete temporary loaded bitmap since it shouldn't be needed
    delete tempbmp;

    // delete the file itself, too bad the file is locked
    int theresult = remove(tocharptr(fileanddir)); 
    // returns -1, also: manually deleting at this point gives the error
    // that the file is being used by another person/program

Any idea how I can load a bitmap or somehow copy it to memory so the file itself wouldn't be locked ?
(So i can delete it a moment after loading it)

Answer 1

You can do it this way

Gdiplus::Bitmap* LoadImageFromFileWithoutLocking(const WCHAR* fileName) {
    using namespace Gdiplus;
    Bitmap src( fileName );
    if ( src.GetLastStatus() != Ok ) {
        return 0;
    }
    Bitmap *dst = new Bitmap(src.GetWidth(), src.GetHeight(), PixelFormat32bppARGB);

    BitmapData srcData;
    BitmapData dstData;
    Rect rc(0, 0, src.GetWidth(), src.GetHeight());

    if (src.LockBits(& rc, ImageLockModeRead, PixelFormat32bppARGB, & srcData) == Ok)
    {
        if ( dst->LockBits(& rc, ImageLockModeWrite, PixelFormat32bppARGB, & dstData) == Ok ) {
            uint8_t * srcBits = (uint8_t *) srcData.Scan0;
            uint8_t * dstBits = (uint8_t *) dstData.Scan0;
            unsigned int stride;
            if (srcData.Stride > 0) { 
                stride = srcData.Stride;
            } else {
                stride = - srcData.Stride;
            }
            memcpy(dstBits, srcBits, src.GetHeight() * stride);

            dst->UnlockBits(&dstData);
        }
        src.UnlockBits(&srcData);
    }
    return dst;
}