关于HBITMAP的问题，请专家指点，谢谢

[sinfee]

我从剪贴板获得了一个HBITMAP的数据，也可以显示，可是如何知道其大小呢，如何转化为void*的指针，
或是拷贝到另外一个内存BUFFER中呢？
我使用了GlobalLock()得到是0，用GlobakSize()也得到是0，可是明明可以显示的？

请大家帮忙，解决问题一定加分。

[sinfee]

我用的是
HBITMAP hBmp=(HBITMAP)::GetClipboardData(CF_BITMAP);
获得的HBITMAP。

[快乐鹦鹉]

CBitmap *pBmp = CBitmap::FromHandle(hBmp);
BITMAP bm;
pBmp->GetBitmap(&bm);
bm中就有大小了
typedef struct tagBITMAP { /* bm */
int bmType;
int bmWidth;
int bmHeight;
int bmWidthBytes;
BYTE bmPlanes;
BYTE bmBitsPixel;
LPVOID bmBits;
} BITMAP;

[token_lys]

不用MFC的方法：

BITMAP bmp;

if (GetObject(hBmp,sizeof(bmp),&bmp))
{
bmp.bmWidth;//宽度
bmp.bmHeight;//高度
}

[sinfee]

bmBits是指的缓冲区指针吗？那么缓冲区有多大呢？

我准备把全部信息存入数据库中，再读出来要还原成HBITMAP或是CBitmap*的，

应该如何做呢？

我刚刚跟踪发现实现上剪贴板中的数据是CF_DIB类型的，可是强行用CF_BITMAP也能获得，
不过用GlobalSize什么的就会提示句柄无效了。

[老夏Max]

参考：
void CCreateRandomBMPDlg::OnBtnTest()
{
// TODO: Add your control notification handler code here
HBITMAP hBmp;

CFileDialog dlg(TRUE, "bmp", NULL, 0, "位图文件 (*.bmp)|*.bmp||", this);

if (dlg.DoModal() != IDOK)
{
return;
}

hBmp = (HBITMAP) LoadImage(NULL, dlg.GetPathName(), IMAGE_BITMAP, 0, 0,
LR_LOADFROMFILE | LR_CREATEDIBSECTION);

if (hBmp == NULL)
{
return;
}

BITMAP bm;
PBITMAPINFO bmpInf;

if (GetObject(hBmp, sizeof(bm), &bm) == 0)
return ;

int nPaletteSize = 0;

if (bm.bmBitsPixel < 16)
nPaletteSize = (int) pow(2, bm.bmBitsPixel);

bmpInf = (PBITMAPINFO) LocalAlloc(LPTR,
sizeof(BITMAPINFOHEADER) +
sizeof(RGBQUAD) * nPaletteSize);

//-----------------------------------------------
bmpInf->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
bmpInf->bmiHeader.biWidth = bm.bmWidth;
bmpInf->bmiHeader.biHeight = bm.bmHeight;
bmpInf->bmiHeader.biPlanes = bm.bmPlanes;
bmpInf->bmiHeader.biBitCount = bm.bmBitsPixel;
bmpInf->bmiHeader.biCompression = BI_RGB;
bmpInf->bmiHeader.biSizeImage = (bm.bmWidth + 7) /
8 * bm.bmHeight * bm.bmBitsPixel;
bmpInf->bmiHeader.biXPelsPerMeter = 0;
bmpInf->bmiHeader.biYPelsPerMeter = 0;
bmpInf->bmiHeader.biClrUsed = 0;
bmpInf->bmiHeader.biClrImportant = 0;
//-----------------------------------------------

HDC hDC = ::GetWindowDC(NULL);
if (!::GetDIBits(hDC, hBmp, 0, (WORD) bm.bmHeight, NULL, bmpInf,
DIB_RGB_COLORS))
{
LocalFree(bmpInf);
::ReleaseDC(NULL, hDC);
return ;
}

void* buf = (void*) new char[bmpInf->bmiHeader.biSizeImage];
if (buf == NULL)
{
::ReleaseDC(NULL, hDC);
LocalFree(bmpInf);
return ;
}

if (!::GetDIBits(hDC, hBmp, 0, (UINT) bm.bmHeight, buf, bmpInf,
DIB_RGB_COLORS))
{
::ReleaseDC(NULL, hDC);
delete[]buf;
LocalFree(bmpInf);
return ;
}

::ReleaseDC(NULL, hDC);

CString sMsg;
sMsg.Format("BitsPixel:%d,width:%d,height:%d", bm.bmBitsPixel, bm.bmWidth,
bm.bmHeight);

AfxMessageBox(sMsg);

CClientDC dc(this);

if (bm.bmBitsPixel == 8)
{
BYTE* pData = (BYTE*) buf;

int nWidth = bm.bmWidth;
while (nWidth % 4 != 0)
{
//Bmp每行数据都是4个字节的整数倍。
nWidth++;
}

for (int i = 0; i < bm.bmHeight; i++)
{
for (int j = 0; j < bm.bmWidth; j++)
{
RGBQUAD rgbQ;
rgbQ = bmpInf->bmiColors[pData[i * nWidth + j]];
dc.SetPixel(j, bm.bmHeight - i,
RGB(rgbQ.rgbRed, rgbQ.rgbGreen, rgbQ.rgbBlue));
}
}
}
else if (bm.bmBitsPixel == 16)
{
BYTE* pData = (BYTE*) buf;

int nWidth = bm.bmWidth*2;
while (nWidth % 4 != 0)
{
nWidth++;
}

BYTE red, green, blue;

for (int i = 0; i < bm.bmHeight; i++)
{
for (int j = 0; j < bm.bmWidth; j++)
{
blue = pData[i * nWidth + j * 2] & 0x1F;
green = pData[i * nWidth + j * 2] >> 5;
green |= (pData[i * nWidth + j * 2 + 1] & 0x03) << 3;
red = (pData[i * nWidth + j * 2 + 1] >> 2) & 0x1F;

WORD wRed = red*8;
WORD wBlue = blue*8;
WORD wGreen = green*8;

red = min(255, wRed);
blue = min(255, wBlue);
green = min(255, wGreen);

dc.SetPixel(j, bm.bmHeight - i, RGB(red, green, blue));
}
}
}
else if (bm.bmBitsPixel == 24)
{
BYTE* pData = (BYTE*) buf;

int nWidth = bm.bmWidth*3;
while (nWidth % 4 != 0)
{
nWidth++;
}

for (int i = 0; i < bm.bmHeight; i++)
{
for (int j = 0; j < bm.bmWidth; j++)
{
dc.SetPixel(j, bm.bmHeight -
i,
RGB(pData[i * nWidth + j * 3 + 2],
pData[i * nWidth + j * 3 + 1],
pData[i * nWidth + j * 3]));
}
}
}
else if (bm.bmBitsPixel == 32)
{
BYTE* pData = (BYTE*) buf;

int nWidth = bm.bmWidth*4;

for (int i = 0; i < bm.bmHeight; i++)
{
for (int j = 0; j < bm.bmWidth; j++)
{
dc.SetPixel(j, bm.bmHeight -
i,
RGB(pData[i * nWidth + j * 4 + 2],
pData[i * nWidth + j * 4 + 1],
pData[i * nWidth + j * 4]));
}
}
}

delete[]buf;

DeleteObject(hBmp);
LocalFree(bmpInf);
}

[sinfee]

虽然没有解决问题，可是依然感谢大家。