C# IShellFolder.GetUIObjectOf方法代码示例

 public static ExtractIconWrapper FromShellFolder(IShellFolder folder, IntPtr pidl)
 {
     if (folder == null)
     {
         throw new ArgumentNullException("folder");
     }
     if (pidl == IntPtr.Zero)
     {
         throw new ArgumentException("pidl == IntPtr.Zero", "pidl");
     }
     try
     {
         object obj2;
         IntPtr[] apidl = new IntPtr[] { pidl };
         folder.GetUIObjectOf(IntPtr.Zero, 1, apidl, typeof(IExtractIconW).GUID, IntPtr.Zero, out obj2);
         if (obj2 != null)
         {
             return new ExtractIconWrapper((IExtractIconW) obj2);
         }
     }
     catch (FileNotFoundException)
     {
     }
     return null;
 }

        private static bool GetContextMenuInterfaces(IShellFolder oParentFolder, IntPtr PIDLs, out IntPtr ctxMenuPtr)
        {
            var arrPidLs = new IntPtr[1];
            arrPidLs[0] = PIDLs;
            var nResult = oParentFolder.GetUIObjectOf(IntPtr.Zero, (uint) arrPidLs.Length, arrPidLs, ref _iidIContextMenu, IntPtr.Zero, out ctxMenuPtr);
            if (SOk == nResult)
            {
                _oContextMenu = (IContextMenu) Marshal.GetTypedObjectForIUnknown(ctxMenuPtr, typeof (IContextMenu));

                return true;
            }
            ctxMenuPtr = IntPtr.Zero;
            _oContextMenu = null;
            return false;
        }

        /// <summary>Gets the interfaces to the context menu</summary>
        /// <param name="oParentFolder">Parent folder</param>
        /// <param name="arrPIDLs">PIDLs</param>
        /// <returns>true if it got the interfaces, otherwise false</returns>
        private bool GetContextMenuInterfaces(IShellFolder oParentFolder, IntPtr[] arrPIDLs, out IntPtr ctxMenuPtr)
        {
            int nResult = oParentFolder.GetUIObjectOf(
                IntPtr.Zero,
                (uint)arrPIDLs.Length,
                arrPIDLs,
                ref IID_IContextMenu,
                IntPtr.Zero,
                out ctxMenuPtr);

            if (S_OK == nResult)
            {
                _oContextMenu = (IContextMenu)Marshal.GetTypedObjectForIUnknown(ctxMenuPtr, typeof(IContextMenu));

                return true;
            }
            else
            {
                ctxMenuPtr = IntPtr.Zero;
                _oContextMenu = null;
                return false;
            }
        }

        /// <summary>Gets the interfaces to the context menu</summary>
        /// <param name="oParentFolder">Parent folder</param>
        /// <param name="arrPIDLs">PIDLs</param>
        /// <returns>true if it got the interfaces, otherwise false</returns>
        private bool GetContextMenuInterfaces(IShellFolder oParentFolder, IntPtr[] arrPIDLs)
        {
            IntPtr pUnknownContextMenu = IntPtr.Zero;

            int nResult = oParentFolder.GetUIObjectOf(
                IntPtr.Zero,
                (uint)arrPIDLs.Length,
                arrPIDLs,
                ref IID_IContextMenu,
                IntPtr.Zero,
                out pUnknownContextMenu);

            if (S_OK == nResult)
            {
                _oContextMenu = (IContextMenu)Marshal.GetTypedObjectForIUnknown(pUnknownContextMenu, typeof(IContextMenu));

                IntPtr pUnknownContextMenu2 = IntPtr.Zero;
                if (S_OK == Marshal.QueryInterface(pUnknownContextMenu, ref IID_IContextMenu2, out pUnknownContextMenu2))
                {
                    _oContextMenu2 = (IContextMenu2)Marshal.GetTypedObjectForIUnknown(pUnknownContextMenu2, typeof(IContextMenu2));
                }
                IntPtr pUnknownContextMenu3 = IntPtr.Zero;
                if (S_OK == Marshal.QueryInterface(pUnknownContextMenu, ref IID_IContextMenu3, out pUnknownContextMenu3))
                {
                    _oContextMenu3 = (IContextMenu3)Marshal.GetTypedObjectForIUnknown(pUnknownContextMenu3, typeof(IContextMenu3));
                }

                return true;
            }
            else
            {
                return false;
            }
        }

        /// <summary>
        /// Retrieves the IContextMenu for specific items
        /// </summary>
        /// <param name="parent">the parent IShellFolder which contains the items</param>
        /// <param name="pidls">the pidls of the items for which to retrieve the IContextMenu</param>
        /// <param name="icontextMenuPtr">the pointer to the IContextMenu</param>
        /// <param name="iContextMenu">the IContextMenu for the items</param>
        /// <returns>true if the IContextMenu has been retrieved succesfully, false otherwise</returns>
        public static bool GetIContextMenu(
            IShellFolder parent,
            IntPtr[] pidls,
            out IntPtr iContextMenuPtr,
            out IContextMenu iContextMenu)
        {
            if (parent.GetUIObjectOf(
                        IntPtr.Zero,
                        (uint)pidls.Length,
                        pidls,
                        ref ShellAPI.IID_IContextMenu,
                        IntPtr.Zero,
                        out iContextMenuPtr) == ShellAPI.S_OK)
            {
                iContextMenu =
                    (IContextMenu)Marshal.GetTypedObjectForIUnknown(
                        iContextMenuPtr, typeof(IContextMenu));

                return true;
            }
            else
            {
                iContextMenuPtr = IntPtr.Zero;
                iContextMenu = null;

                return false;
            }
        }

    private bool getThumbnail(string file, IntPtr pidl, IShellFolder item)
    {
      IntPtr hBmp = IntPtr.Zero;
      IExtractImage extractImage = null;

      try
      {
        string pidlPath = PathFromPidl(pidl);
        if (Path.GetFileName(pidlPath).ToUpperInvariant().Equals(Path.GetFileName(file).ToUpperInvariant()))
        {
          // we have the item:
          IUnknown iunk = null;
          int prgf = 0;
          Guid iidExtractImage = new Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1");
          item.GetUIObjectOf(IntPtr.Zero, 1, ref pidl, ref iidExtractImage, out prgf, ref iunk);
          extractImage = (IExtractImage)iunk;

          if (extractImage != null)
          {
            //Got an IExtractImage object!
            SIZE sz = new SIZE();
            sz.cx = desiredSize.Width;
            sz.cy = desiredSize.Height;
            StringBuilder location = new StringBuilder(260, 260);
            int priority = 0;
            int requestedColourDepth = 32;
            //EIEIFLAG flags = EIEIFLAG.IEIFLAG_ASPECT | EIEIFLAG.IEIFLAG_SCREEN;
            EIEIFLAG flags = EIEIFLAG.IEIFLAG_ORIGSIZE | EIEIFLAG.IEIFLAG_ASPECT | EIEIFLAG.IEIFLAG_QUALITY;
            int uFlags = (int)flags;

            // E.g. for PDFs on Vista...
            try
            {
              extractImage.GetLocation(location, location.Capacity, ref priority, ref sz, requestedColourDepth,
                                       ref uFlags);
            }
            catch (Exception) {}

            extractImage.Extract(out hBmp);
            if (hBmp != IntPtr.Zero)
            {
              // create the image object:
              thumbNail = System.Drawing.Bitmap.FromHbitmap(hBmp);
              // is thumbNail owned by the Bitmap?
            }

            Marshal.ReleaseComObject(extractImage);
            extractImage = null;
          }
          return true;
        }
        else
        {
          return false;
        }
      }
      catch (Exception ex)
      {
        if (hBmp != IntPtr.Zero)
        {
          UnManagedMethods.DeleteObject(hBmp);
        }
        if (extractImage != null)
        {
          Marshal.ReleaseComObject(extractImage);
        }
        throw ex;
      }
    }

 private static IContextMenu GetContextMenu(IWin32Window owner, IShellFolder parent, string[] fileNames)
 {
     IContextMenu menu;
     IntPtr[] apidl = new IntPtr[fileNames.Length];
     try
     {
         for (int i = 0; i < fileNames.Length; i++)
         {
             apidl[i] = parent.ParseDisplayName(owner.Handle, fileNames[i]);
         }
         menu = parent.GetUIObjectOf<IContextMenu>(owner.Handle, apidl);
     }
     finally
     {
         foreach (IntPtr ptr in apidl)
         {
             if (ptr != IntPtr.Zero)
             {
                 Marshal.FreeCoTaskMem(ptr);
             }
         }
     }
     return menu;
 }

        private bool GetThumbnail(string file, IntPtr pidl, IShellFolder item)
        {
            IntPtr bmp = IntPtr.Zero;
            IExtractImage extractImage = null;

            try
            {
                string pidlPath = PathFromPidl(pidl);
                if (Path.GetFileName(pidlPath).ToUpper().Equals(Path.GetFileName(file).ToUpper()))
                {
                    // we have the item:
                    IUnknown iunk = null;
                    int prgf;
                    Guid iidExtractImage = new Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1");
                    item.GetUIObjectOf(IntPtr.Zero, 1, ref pidl, ref iidExtractImage, out prgf, ref iunk);
                    extractImage = (IExtractImage)iunk;

                    if (extractImage != null)
                    {
                        //Got an IExtractImage object!
                        ShellAPI.SIZE size = new ShellAPI.SIZE { cx = this.DesiredSize.Width, cy = this.DesiredSize.Height };
                        StringBuilder location = new StringBuilder(260, 260);
                        int priority = 0;
                        const int requestedColourDepth = 32;
                        const IEIFLAG flags = IEIFLAG.IEIFLAG_ASPECT | IEIFLAG.IEIFLAG_SCREEN;
                        int uFlags = (int)flags;

                        extractImage.GetLocation(location, location.Capacity, ref priority, ref size, requestedColourDepth, ref uFlags);

                        extractImage.Extract(out bmp);
                        if (bmp != IntPtr.Zero)
                        {
                            // create the image object:
                            this.ThumbNail = Image.FromHbitmap(bmp);
                            // is thumbNail owned by the Bitmap?
                        }

                        Marshal.ReleaseComObject(extractImage);
                        extractImage = null;
                    }
                    return true;
                }
                else
                {
                    return false;
                }
            }
            catch (Exception)
            {
                if (bmp != IntPtr.Zero)
                {
                    UnManagedMethods.DeleteObject(bmp);
                }
                if (extractImage != null)
                {
                    Marshal.ReleaseComObject(extractImage);
                }

                throw;
            }
        }

        private bool getThumbNail(string file, IntPtr pidl, IShellFolder item)
        {
            IntPtr hBmp = IntPtr.Zero;
            IExtractImage extractImage = null;
            try
            {
                var pidlPath = pathFromPidl(pidl);
                if (!Path.GetFileName(pidlPath).ToUpper().Equals(Path.GetFileName(file).ToUpper()))
                {
                    return false;
                }

                IUnknown iunk = null;
                var prgf = 0;
                var iidExtractImage = new Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1");
                item.GetUIObjectOf(IntPtr.Zero, 1, ref pidl, ref iidExtractImage, ref prgf, ref iunk);
                extractImage = (IExtractImage)iunk;
                if (extractImage == null)
                {
                    return true;
                }

                var sz = new Size { cx = DesiredSize.Width, cy = DesiredSize.Height };
                var location = new StringBuilder(260, 260);
                var priority = 0;
                const int requestedColourDepth = 32;
                const EIEIFLAG flags =
                    EIEIFLAG.IeiflagScreen | EIEIFLAG.IeiflagAsync | EIEIFLAG.IeiflagQuality | EIEIFLAG.IeiflagCache;
                var uFlags = (int)flags;
                try
                {
                    extractImage.GetLocation(
                        location, location.Capacity, ref priority, ref sz, requestedColourDepth, ref uFlags);
                }
                catch { }

                extractImage.Extract(ref hBmp);

                if (hBmp != IntPtr.Zero)
                {
                    ThumbNail = Image.FromHbitmap(hBmp);
                }

                Marshal.ReleaseComObject(extractImage);
                extractImage = null;
                return true;
            }
            finally
            {
                if (hBmp != IntPtr.Zero)
                {
                    UnmanagedMethods.DeleteObject(hBmp);
                }
                if (extractImage != null)
                {
                    Marshal.ReleaseComObject(extractImage);
                }
            }
        }

        private bool GetThumbnailHelper(string file, IntPtr pidl, IShellFolder item)
        {
            IntPtr bitmapPointer = IntPtr.Zero;

            IExtractImage extractImage = null;

            try
            {
                string pidlPath = this.PathFromPidl(pidl);

                if (Path.GetFileName(pidlPath).ToUpper().Equals(Path.GetFileName(file).ToUpper()))
                {
                    IUnknown iunk = null;
                    int prgf = 0;
                    Guid iidExtractImage = new Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1");
                    item.GetUIObjectOf(IntPtr.Zero, 1, ref pidl, ref iidExtractImage, ref prgf, ref iunk);
                    extractImage = (IExtractImage)iunk;
                    if (extractImage != null)
                    {
                        Console.WriteLine("Got an IExtractImage object - " + file);
                        SIZE sz = new SIZE();
                        sz.HorizontalSize = this.DesiredSize.Width;
                        sz.VerticalSize = this.DesiredSize.Height;
                        StringBuilder location = new StringBuilder(260, 260);
                        int priority = 0;
                        int requestedColourDepth = 32;
                        EIEIFLAG flags = EIEIFLAG.IEIFLAG_ASPECT | EIEIFLAG.IEIFLAG_SCREEN;
                        int nameFlags = (int)flags;
                        extractImage.GetLocation(location, location.Capacity, ref priority, ref sz, requestedColourDepth, ref nameFlags);
                        extractImage.Extract(ref bitmapPointer);

                        if (bitmapPointer != IntPtr.Zero)
                        {
                            this.thumbNail = Bitmap.FromHbitmap(bitmapPointer);
                        }

                        Marshal.ReleaseComObject(extractImage);

                        extractImage = null;
                    }

                    return true;
                }
                else
                {
                    return false;
                }
            }
            catch (Exception ex)
            {
                if (bitmapPointer != IntPtr.Zero)
                {
                    UnmanagedMethods.DeleteObject(bitmapPointer);
                }

                if (extractImage != null)
                {
                    Marshal.ReleaseComObject(extractImage);
                }

                throw ex;
            }
        }

            private bool GetThumbnail(string file, IntPtr pidl, IShellFolder item, int width, int height)
            {
                IntPtr hBmp = IntPtr.Zero;
                IExtractImage extractImage = null;

                try
                {
                    string pidlPath = PathFromPidl(pidl);
                    if (Path.GetFileName(pidlPath).ToUpper().Equals(Path.GetFileName(file).ToUpper()))
                    {
                        IUnknown iunk = null;
                        int prgf = 0;
                        Guid iidExtractImage = new Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1");
                        item.GetUIObjectOf(IntPtr.Zero, 1, ref pidl, ref iidExtractImage, out prgf, ref iunk);
                        extractImage = (IExtractImage)iunk;

                        if (extractImage != null)
                        {
                            SIZE sz = new SIZE();
                            sz.cx = width;
                            sz.cy = height;
                            StringBuilder location = new StringBuilder(260, 260);
                            int priority = 0;
                            int requestedColourDepth = 32;
                            EIEIFLAG flags = EIEIFLAG.IEIFLAG_ASPECT | EIEIFLAG.IEIFLAG_SCREEN;
                            int uFlags = (int)flags;

                            extractImage.GetLocation(location, location.Capacity, ref priority, ref sz, requestedColourDepth, ref uFlags);

                            extractImage.Extract(out hBmp);
                            if (hBmp != IntPtr.Zero)
                            {
                                thumbNail = System.Drawing.Bitmap.FromHbitmap(hBmp);
                            }

                            Marshal.ReleaseComObject(extractImage);
                            extractImage = null;
                        }
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
                catch (Exception ex)
                {
                    if (hBmp != IntPtr.Zero)
                    {
                        UnmanagedMethods.DeleteObject(hBmp);
                    }
                    if (extractImage != null)
                    {
                        Marshal.ReleaseComObject(extractImage);
                    }
                    throw ex;
                }
            }

        /// <summary>
        /// This method will use the GetUIObjectOf method of IShellFolder to obtain the IDropTarget of a
        /// ShellItem. 
        /// </summary>
        /// <param name="item">The item for which to obtain the IDropTarget</param>
        /// <param name="dropTargetPtr">A pointer to the returned IDropTarget</param>
        /// <returns>the IDropTarget from the ShellItem</returns>
        public static bool GetIDropTarget(IntPtr[] pidls, IShellFolder parent, out IntPtr dropTargetPtr, out ShellDll.IDropTarget dropTarget)
        {
            if (parent.GetUIObjectOf(
                    IntPtr.Zero,
                    1,
                    pidls,
                    ref ShellAPI.IID_IDropTarget,
                    IntPtr.Zero,
                    out dropTargetPtr) == ShellAPI.S_OK)
            {
                dropTarget =
                    (ShellDll.IDropTarget)Marshal.GetTypedObjectForIUnknown(dropTargetPtr, typeof(ShellDll.IDropTarget));

                return true;
            }
            else
            {
                dropTarget = null;
                dropTargetPtr = IntPtr.Zero;
                return false;
            }
        }

 /// <summary>
 /// This method will use the GetUIObjectOf method of IShellFolder to obtain the IDataObject of a
 /// ShellItem. 
 /// </summary>
 /// <returns>the IDataObject the ShellItem</returns>
 public static IntPtr GetIDataObject(IntPtr[] pidls, IShellFolder parent)
 {
     IntPtr dataObjectPtr;
     if (parent.GetUIObjectOf(
             IntPtr.Zero,
             (uint)pidls.Length,
             pidls,
             ref ShellAPI.IID_IDataObject,
             IntPtr.Zero,
             out dataObjectPtr) == ShellAPI.S_OK)
     {
         return dataObjectPtr;
     }
     else
     {
         return IntPtr.Zero;
     }
 }

        private bool _getThumbNail(string file, IntPtr pidl, IShellFolder item)
        {
            IntPtr hBmp = IntPtr.Zero;
            IExtractImage extractImage = null;
            IntPtr[] pidl_array = new IntPtr[] { pidl };
            try
            {
            string pidlPath = PathFromPidl(pidl);
            if (Path.GetFileName(pidlPath).ToUpper().Equals(Path.GetFileName(file).ToUpper()))
            {
                object iunk = null;
                Guid iidExtractImage = new Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1");
                item.GetUIObjectOf(IntPtr.Zero, 1, pidl_array, ref iidExtractImage, IntPtr.Zero, out iunk);
                extractImage = (IExtractImage)iunk;
                if (extractImage != null)
                {
                    Console.WriteLine("Got an IExtractImage object!");
                    SIZE sz = new SIZE();
                    sz.cx = DesiredSize.Width;
                    sz.cy = DesiredSize.Height;
                    StringBuilder location = new StringBuilder(260, 260);
                    int priority = 0;
                    int requestedColourDepth = 32;
                    EIEIFLAG flags = EIEIFLAG.IEIFLAG_ASPECT | EIEIFLAG.IEIFLAG_SCREEN;
                    int uFlags = (int)flags;
                    extractImage.GetLocation(location, location.Capacity, ref priority, ref sz, requestedColourDepth, ref uFlags);
                    extractImage.Extract(ref hBmp);
                    if (hBmp != IntPtr.Zero)
                    {
                        _thumbNail = Bitmap.FromHbitmap(hBmp);
                    }
                    Marshal.ReleaseComObject(extractImage);
                    extractImage = null;
                }
                return true;
            }
            else
            {
                return false;
            }
            }
            catch (Exception ex)
            {
            if (hBmp != IntPtr.Zero)
            {
                UnmanagedMethods.DeleteObject(hBmp);
            }
            if (extractImage != null)
            {
                Marshal.ReleaseComObject(extractImage);
            }

            throw ex;
            }
        }