如何将HIMAGELIST的IntPtr转换为位图/图像

Question

我正在尝试使用非托管dll中的HIMAGELIST，它将结果作为IntPtr。

我有办法将此IntPtr转换为位图或图像，以便将其用于Winforms按钮，如：

myButton.Image = intPtrImage

Answer 1

您需要为列表中的每个图片调用ImageList_GetIcon - 这会为您提供一个很容易加载到Bitmap

的HICON

Answer 2

使用此功能：

private const string Gdi32Dll = @".\gdi32.dll";
[DllImport(Gdi32Dll, ExactSpelling = true)]
internal static extern int SetDIBitsToDevice(
                                                  IntPtr hdc,
                                                  int xdst,
                                                  int ydst,
                                                  int width,
                                                  int height,
                                                  int xsrc,
                                                  int ysrc,
                                                  int start,
                                                  int lines,
                                                  IntPtr bitsptr,
                                                  IntPtr bmiptr,
                                                  int color);
public static Bitmap BitmapFromDIB(IntPtr dibPtrArg)
{
   Bitmapinfoheader bmiHeader;
   IntPtr pixptr = IntPtr.Zero;
   GetPixelInfo(dibPtrArg, out pixptr, out bmiHeader);
   Bitmap bitMap = new Bitmap(bmiHeader.biWidth, bmiHeader.biHeight);
   Graphics scannedImageGraphics = Graphics.FromImage(bitMap);
   IntPtr hdc = scannedImageGraphics.GetHdc();
   SetDIBitsToDevice(
       hdc,
       0, // XDest
       0, // YDest
       bmiHeader.biWidth,
       bmiHeader.biHeight,
       0, // XSrc
       0, // YSrc
       0, // uStartScan
       bmiHeader.biHeight, // cScanLines
       pixptr, // lpvBits
       dibPtrArg, // lpbmi
       DibRgbColors); // 0 = literal RGB values rather than palette
   scannedImageGraphics.ReleaseHdc(hdc);
   return bitMap;
}

private static void GetPixelInfo(IntPtr bmpptr, out IntPtr pix, out Bitmapinfoheader bmi)
{
   bmi = new Bitmapinfoheader();
   Marshal.PtrToStructure(bmpptr, bmi); // copy into struct.
   if (bmi.biSizeImage == 0)
   {
       bmi.biSizeImage = ((((bmi.biWidth * bmi.biBitCount) + 31) & ~31) >> 3) *        bmi.biHeight;

   }
   int p = bmi.biClrUsed;
   if ((p == 0) && (bmi.biBitCount <= 8))
   {
       p = 1 << bmi.biBitCount;
   }
   pix = (IntPtr)((p * 2) + bmi.biSize + (int)bmpptr);
}