我作了一个小的画图程序，如何将它DC上画的图存成一张位图？

[zx197093]

有什么简单的办法，请给一点源码。谢谢

[ddszhan]

GetDIBits();
设置相应的BITMAPFILEHEADER等，然后写文件.

[zx197093]

大家帮我看下程序，为何截的图不能在资源管理器中预览缩略图？

CRect rect;
GetDlgItem(IDC_Draw)->GetWindowRect(rect);
(GetDlgItem(IDC_Draw)->GetParent())->ScreenToClient(rect);

CWindowDC dc(GetDlgItem(IDC_Draw));

BITMAPINFO bi;
void *pBits=NULL;
int nWidth=rect.right;
int nHeight=rect.bottom;
ZeroMemory(&bi,sizeof(bi));
bi.bmiHeader.biSize=sizeof(bi.bmiHeader);
bi.bmiHeader.biHeight=nHeight;
bi.bmiHeader.biWidth=nWidth;
bi.bmiHeader.biPlanes=1;
bi.bmiHeader.biBitCount=24;
bi.bmiHeader.biCompression=BI_RGB;
bi.bmiHeader.biSizeImage=3*nWidth*nHeight;
HDC hDesktopCompatibleDC=::GetDC(GetDlgItem(IDC_Draw)->GetSafeHwnd());
HDC hBmpFileDC=CreateCompatibleDC(hDesktopCompatibleDC);
HBITMAP hBmpFileBitmap=CreateDIBSection(hDesktopCompatibleDC,&bi,DIB_RGB_COLORS,&pBits,NULL,0);
SelectObject(hBmpFileDC,hBmpFileBitmap);
BitBlt(hBmpFileDC,0,0,nWidth,nHeight,hDesktopCompatibleDC,0,0,SRCCOPY);

HANDLE hFile=CreateFile("test.bmp",GENERIC_WRITE,FILE_SHARE_WRITE,NULL,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
if(hFile!=INVALID_HANDLE_VALUE)
{
DWORD dwRet=0;
BITMAPFILEHEADER bmfHeader;
ZeroMemory(&bmfHeader,sizeof(bmfHeader));
bmfHeader.bfOffBits=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
bmfHeader.bfSize=bi.bmiHeader.biSizeImage+bmfHeader.bfOffBits;
bmfHeader.bfType='MB';

WriteFile(hFile,&bmfHeader,sizeof(bmfHeader),&dwRet,NULL);
WriteFile(hFile,&bi.bmiHeader,sizeof(bi.bmiHeader),&dwRet,NULL);
WriteFile(hFile,pBits,bi.bmiHeader.biSizeImage,&dwRet,NULL);
CloseHandle(hFile);
}

DeleteDC(hBmpFileDC);
DeleteObject(hBmpFileBitmap);

[HillFrog]

BMP文件的每一行是要求32BIT行对齐的，即如果一行的像素数据是787字节，必须补零延长到788字节。（788/4 = 197）你的程序好象没做这个工作。另外pBits好象要先申请内存才能用。

[mary1985]

WAHAT ARE YOU SAY ,I DO NOT KNOWN!!!!!!!!