解决了！有关工作代码，请参见 EDIT 2。
根据该站点的代码和 freundblase 在同一站点中所做的评论，我有以下类来获取基于文件扩展名的巨型默认图标：
// Original bad code removed
我正在尝试通过以下方式使用该类：
preview.ImageSource = IconManager.GetIcon(".pdf", true);
其中 preview 是一个 ImageBrush 对象。
但我得到以下图像：
是的，我尝试使用注册的文件类型，如 pdf 文件。
怎么了？
TIA
-
编辑1：
我认为该图标用于未注册的文件类型。
如果我使用实际文件，我会得到 FileNotFoundException。
-
编辑2：
在发布这个问题之前，我使用 ReSharper 进行了代码清理。
我根据站点代码和 freundblase 评论再次制作了课程，现在它正在工作！
我必须仔细分析 ReSharper 所做的更改。代码清理从来没有给我任何问题。
对于后代，以下代码有效：
public class IconManager
{
// Constants that we need in the function call
private const int SHGFI_ICON = 0x100;
private const int SHGFI_LARGEICON = 0x0;
private const int SHGFI_SMALLICON = 0x1;
private const int SHIL_EXTRALARGE = 0x2;
private const int SHIL_JUMBO = 0x4;
private const int WM_CLOSE = 0x0010;
// This structure will contain information about the file
public struct SHFILEINFO
{
// Handle to the icon representing the file
public IntPtr hIcon;
// Index of the icon within the image list
public int iIcon;
// Various attributes of the file
public uint dwAttributes;
// Path to the file
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)] public string szDisplayName;
// File type
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)] public string szTypeName;
};
[DllImport("Kernel32.dll")]
public static extern Boolean CloseHandle(IntPtr handle);
private struct IMAGELISTDRAWPARAMS
{
public int cbSize;
public IntPtr himl;
public int i;
public IntPtr hdcDst;
public int x;
public int y;
public int cx;
public int cy;
public int xBitmap; // x offest from the upperleft of bitmap
public int yBitmap; // y offset from the upperleft of bitmap
public int rgbBk;
public int rgbFg;
public int fStyle;
public int dwRop;
public int fState;
public int Frame;
public int crEffect;
}
[DllImport("user32")]
private static extern
IntPtr SendMessage(
IntPtr handle,
int Msg,
IntPtr wParam,
IntPtr lParam
);
[StructLayout(LayoutKind.Sequential)]
private struct IMAGEINFO
{
private readonly IntPtr hbmImage;
private readonly IntPtr hbmMask;
private readonly int Unused1;
private readonly int Unused2;
private readonly RECT rcImage;
}
#region Private ImageList COM Interop (XP)
[ComImport]
[Guid("46EB5926-582E-4017-9FDF-E8998DAA0950")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
//helpstring("Image List"),
private interface IImageList
{
[PreserveSig]
int Add(
IntPtr hbmImage,
IntPtr hbmMask,
ref int pi);
[PreserveSig]
int ReplaceIcon(
int i,
IntPtr hicon,
ref int pi);
[PreserveSig]
int SetOverlayImage(
int iImage,
int iOverlay);
[PreserveSig]
int Replace(
int i,
IntPtr hbmImage,
IntPtr hbmMask);
[PreserveSig]
int AddMasked(
IntPtr hbmImage,
int crMask,
ref int pi);
[PreserveSig]
int Draw(
ref IMAGELISTDRAWPARAMS pimldp);
[PreserveSig]
int Remove(
int i);
[PreserveSig]
int GetIcon(
int i,
int flags,
ref IntPtr picon);
[PreserveSig]
int GetImageInfo(
int i,
ref IMAGEINFO pImageInfo);
[PreserveSig]
int Copy(
int iDst,
IImageList punkSrc,
int iSrc,
int uFlags);
[PreserveSig]
int Merge(
int i1,
IImageList punk2,
int i2,
int dx,
int dy,
ref Guid riid,
ref IntPtr ppv);
[PreserveSig]
int Clone(
ref Guid riid,
ref IntPtr ppv);
[PreserveSig]
int GetImageRect(
int i,
ref RECT prc);
[PreserveSig]
int GetIconSize(
ref int cx,
ref int cy);
[PreserveSig]
int SetIconSize(
int cx,
int cy);
[PreserveSig]
int GetImageCount(
ref int pi);
[PreserveSig]
int SetImageCount(
int uNewCount);
[PreserveSig]
int SetBkColor(
int clrBk,
ref int pclr);
[PreserveSig]
int GetBkColor(
ref int pclr);
[PreserveSig]
int BeginDrag(
int iTrack,
int dxHotspot,
int dyHotspot);
[PreserveSig]
int EndDrag();
[PreserveSig]
int DragEnter(
IntPtr hwndLock,
int x,
int y);
[PreserveSig]
int DragLeave(
IntPtr hwndLock);
[PreserveSig]
int DragMove(
int x,
int y);
[PreserveSig]
int SetDragCursorImage(
ref IImageList punk,
int iDrag,
int dxHotspot,
int dyHotspot);
[PreserveSig]
int DragShowNolock(
int fShow);
[PreserveSig]
int GetDragImage(
ref POINT ppt,
ref POINT pptHotspot,
ref Guid riid,
ref IntPtr ppv);
[PreserveSig]
int GetItemFlags(
int i,
ref int dwFlags);
[PreserveSig]
int GetOverlayImage(
int iOverlay,
ref int piIndex);
};
#endregion
///
/// SHGetImageList is not exported correctly in XP. See KB316931
/// http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q316931
/// Apparently (and hopefully) ordinal 727 isn't going to change.
///
[DllImport("shell32.dll", EntryPoint = "#727")]
private static extern int SHGetImageList(
int iImageList,
ref Guid riid,
out IImageList ppv
);
// The signature of SHGetFileInfo (located in Shell32.dll)
[DllImport("Shell32.dll")]
public static extern int SHGetFileInfo(string pszPath, int dwFileAttributes, ref SHFILEINFO psfi, int cbFileInfo,
uint uFlags);
[DllImport("Shell32.dll")]
public static extern int SHGetFileInfo(IntPtr pszPath, uint dwFileAttributes, ref SHFILEINFO psfi,
int cbFileInfo, uint uFlags);
[DllImport("shell32.dll", SetLastError = true)]
private static extern int SHGetSpecialFolderLocation(IntPtr hwndOwner, Int32 nFolder, ref IntPtr ppidl);
[DllImport("user32")]
public static extern int DestroyIcon(IntPtr hIcon);
public struct pair
{
public Icon icon { get; set; }
public IntPtr iconHandleToDestroy { set; get; }
}
public static int DestroyIcon2(IntPtr hIcon)
{
return DestroyIcon(hIcon);
}
private static BitmapSource IconSource(Icon ic)
{
var ic2 = Imaging.CreateBitmapSourceFromHIcon(ic.Handle,
Int32Rect.Empty,
BitmapSizeOptions.FromEmptyOptions());
ic2.Freeze();
return ic2;
}
public static BitmapSource IconPath(string FileName, bool small, bool checkDisk, bool addOverlay)
{
var shinfo = new SHFILEINFO();
const uint SHGFI_USEFILEATTRIBUTES = 0x000000010;
const uint SHGFI_LINKOVERLAY = 0x000008000;
uint flags;
if (small)
flags = SHGFI_ICON | SHGFI_SMALLICON;
else
flags = SHGFI_ICON | SHGFI_LARGEICON;
if (!checkDisk)
flags |= SHGFI_USEFILEATTRIBUTES;
if (addOverlay)
flags |= SHGFI_LINKOVERLAY;
var res = SHGetFileInfo(FileName, 0, ref shinfo, Marshal.SizeOf(shinfo), flags);
if (res == 0)
throw (new FileNotFoundException());
var myIcon = Icon.FromHandle(shinfo.hIcon);
var bs = IconSource(myIcon);
myIcon.Dispose();
bs.Freeze(); // importantissimo se no fa memory leak
DestroyIcon(shinfo.hIcon);
CloseHandle(shinfo.hIcon);
return bs;
}
public static BitmapSource GetLargeIcon(string FileName, bool jumbo, bool checkDisk)
{
var shinfo = new SHFILEINFO();
const uint SHGFI_USEFILEATTRIBUTES = 0x000000010;
const uint SHGFI_SYSICONINDEX = 0x4000;
const int FILE_ATTRIBUTE_NORMAL = 0x80;
var flags = SHGFI_SYSICONINDEX;
if (!checkDisk) // This does not seem to work. If I try it, a folder icon is always returned.
flags |= SHGFI_USEFILEATTRIBUTES;
var res = SHGetFileInfo(FileName, FILE_ATTRIBUTE_NORMAL, ref shinfo, Marshal.SizeOf(shinfo), flags);
if (res == 0)
throw (new FileNotFoundException());
var iconIndex = shinfo.iIcon;
// Get the System IImageList object from the Shell:
var iidImageList = new Guid("46EB5926-582E-4017-9FDF-E8998DAA0950");
IImageList iml;
var size = jumbo ? SHIL_JUMBO : SHIL_EXTRALARGE;
SHGetImageList(size, ref iidImageList, out iml);
var hIcon = IntPtr.Zero;
const int ILD_TRANSPARENT = 1;
iml.GetIcon(iconIndex, ILD_TRANSPARENT, ref hIcon);
var myIcon = Icon.FromHandle(hIcon);
var bs = IconSource(myIcon);
myIcon.Dispose();
bs.Freeze(); // very important to avoid memory leak
DestroyIcon(hIcon);
SendMessage(hIcon, WM_CLOSE, IntPtr.Zero, IntPtr.Zero);
return bs;
}
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
private readonly int _Left;
private readonly int _Top;
private readonly int _Right;
private readonly int _Bottom;
}
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
public int X;
public int Y;
public POINT(int x, int y)
{
X = x;
Y = y;
}
public static implicit operator Point(POINT p)
{
return new Point(p.X, p.Y);
}
public static implicit operator POINT(Point p)
{
return new POINT(p.X, p.Y);
}
}
}