c# 使用ActiveDesktop實現壁紙切換，適合大部分圖片格式

我的廣告單元，有空點一下哦，謝謝！

操作步驟：首先添加類：using System;using System.Runtime.InteropServices;namespace WorkHelper{    enum WPSTYLE    {        CENTER = 0,        TILE = 1,        STRETCH = 2,        MAX = 3    }    struct WALLPAPEROPT    {        public int dwSize;        public WPSTYLE dwStyle;    }    struct COMPONENTSOPT    {        public int dwSize;        [MarshalAs(UnmanagedType.Bool)]        public bool fEnableComponents;        [MarshalAs(UnmanagedType.Bool)]        public bool fActiveDesktop;    }    struct COMPPOS    {        public const int COMPONENT_TOP = 0x3FFFFFFF;        public const int COMPONENT_DEFAULT_LEFT = 0xFFFF;        public const int COMPONENT_DEFAULT_TOP = 0xFFFF;        public int dwSize;        public int iLeft;        public int iTop;        public int dwWidth;        public int dwHeight;        public int izIndex;        [MarshalAs(UnmanagedType.Bool)]        public bool fCanResize;        [MarshalAs(UnmanagedType.Bool)]        public bool fCanResizeX;        [MarshalAs(UnmanagedType.Bool)]        public bool fCanResizeY;        public int iPreferredLeftPercent;        public int iPreferredTopPercent;    }    [Flags]    enum ITEMSTATE    {        NORMAL = 0x00000001,        FULLSCREEN = 00000002,        SPLIT = 0x00000004,        VALIDSIZESTATEBITS = NORMAL | SPLIT | FULLSCREEN,        VALIDSTATEBITS = NORMAL | SPLIT | FULLSCREEN | unchecked((int)0x80000000) | 0x40000000    }    struct COMPSTATEINFO    {        public int dwSize;        public int iLeft;        public int iTop;        public int dwWidth;        public int dwHeight;        public int dwItemState;    }    enum COMP_TYPE    {        HTMLDOC = 0,        PICTURE = 1,        WEBSITE = 2,        CONTROL = 3,        CFHTML = 4,        MAX = 4    }    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]    struct COMPONENT    {        private const int INTERNET_MAX_URL_LENGTH = 2084;   //   =           // INTERNET_MAX_SCHEME_LENGTH   (32)   +   "://\0".Length   +           // INTERNET_MAX_PATH_LENGTH   (2048)          public int dwSize;        public int dwID;        public COMP_TYPE iComponentType;        [MarshalAs(UnmanagedType.Bool)]        public bool fChecked;        [MarshalAs(UnmanagedType.Bool)]        public bool fDirty;        [MarshalAs(UnmanagedType.Bool)]        public bool fNoScroll;        public COMPPOS cpPos;        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]        public string wszFriendlyName;        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = INTERNET_MAX_URL_LENGTH)]        public string wszSource;        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = INTERNET_MAX_URL_LENGTH)]        public string wszSubscribedURL;#if   AD_IE5         public   int   dwCurItemState;         public   COMPSTATEINFO   csiOriginal;         public   COMPSTATEINFO   csiRestored;   #endif    }    enum DTI_ADTIWUI    {        DTI_ADDUI_DEFAULT = 0x00000000,        DTI_ADDUI_DISPSUBWIZARD = 0x00000001,        DTI_ADDUI_POSITIONITEM = 0x00000002,    }    [Flags]    enum AD_APPLY    {        SAVE = 0x00000001,        HTMLGEN = 0x00000002,        REFRESH = 0x00000004,        ALL = SAVE | HTMLGEN | REFRESH,        FORCE = 0x00000008,        BUFFERED_REFRESH = 0x00000010,        DYNAMICREFRESH = 0x00000020    }    [Flags]    enum COMP_ELEM    {        TYPE = 0x00000001,        CHECKED = 0x00000002,        DIRTY = 0x00000004,        NOSCROLL = 0x00000008,        POS_LEFT = 0x00000010,        POS_TOP = 0x00000020,        SIZE_WIDTH = 0x00000040,        SIZE_HEIGHT = 0x00000080,        POS_ZINDEX = 0x00000100,        SOURCE = 0x00000200,        FRIENDLYNAME = 0x00000400,        SUBSCRIBEDURL = 0x00000800,        ORIGINAL_CSI = 0x00001000,        RESTORED_CSI = 0x00002000,        CURITEMSTATE = 0x00004000,        ALL = TYPE | CHECKED | DIRTY | NOSCROLL | POS_LEFT | SIZE_WIDTH |            SIZE_HEIGHT | POS_ZINDEX | SOURCE |            FRIENDLYNAME | POS_TOP | SUBSCRIBEDURL | ORIGINAL_CSI |            RESTORED_CSI | CURITEMSTATE    }    [Flags]    enum ADDURL    {        SILENT = 0x0001    }    [        ComImport(),        Guid("F490EB00-1240-11D1-9888-006097DEACF9"),        InterfaceType(ComInterfaceType.InterfaceIsIUnknown)    ]    interface IActiveDesktop    {        void ApplyChanges(AD_APPLY dwFlags);        void GetWallpaper([MarshalAs(UnmanagedType.LPWStr)] System.Text.StringBuilder pwszWallpaper, int cchWallpaper, int dwReserved);        void SetWallpaper([MarshalAs(UnmanagedType.LPWStr)]   string pwszWallpaper, int dwReserved);        void GetWallpaperOptions(ref   WALLPAPEROPT pwpo, int dwReserved);        void SetWallpaperOptions([In]   ref   WALLPAPEROPT pwpo, int dwReserved);        void GetPattern([MarshalAs(UnmanagedType.LPWStr)] System.Text.StringBuilder pwszPattern, int cchPattern, int dwReserved);        void SetPattern([MarshalAs(UnmanagedType.LPWStr)]   string pwszPattern, int dwReserved);        void GetDesktopItemOptions(ref   COMPONENTSOPT pco, int dwReserved);        void SetDesktopItemOptions([In]   ref   COMPONENTSOPT pco, int dwReserved);        void AddDesktopItem([In]   ref   COMPONENT pcomp, int dwReserved);        void AddDesktopItemWithUI(IntPtr hwnd, [In]   ref   COMPONENT pcomp, DTI_ADTIWUI dwFlags);        void ModifyDesktopItem([In]   ref   COMPONENT pcomp, COMP_ELEM dwFlags);        void RemoveDesktopItem([In]   ref   COMPONENT pcomp, int dwReserved);        void GetDesktopItemCount(out   int lpiCount, int dwReserved);        void GetDesktopItem(int nComponent, ref   COMPONENT pcomp, int dwReserved);        void GetDesktopItemByID(IntPtr dwID, ref   COMPONENT pcomp, int dwReserved);        void GenerateDesktopItemHtml([MarshalAs(UnmanagedType.LPWStr)] string pwszFileName, [In]   ref   COMPONENT pcomp, int dwReserved);        void AddUrl(IntPtr hwnd, [MarshalAs(UnmanagedType.LPWStr)]   string pszSource, [In]   ref   COMPONENT pcomp, ADDURL dwFlags);        void GetDesktopItemBySource([MarshalAs(UnmanagedType.LPWStr)] string pwszSource, ref   COMPONENT pcomp, int dwReserved);    }    [        ComImport(),        Guid("75048700-EF1F-11D0-9888-006097DEACF9")    ]    class ActiveDesktop   /*   :   IActiveDesktop   */   { }}調用：（終於搞定背景圖片樣式了）public bool SetDeskBg(String filename)        {            try            {                ActiveDesktop ad = new ActiveDesktop();                IActiveDesktop iad = ad as IActiveDesktop;                if (iad != null)                {                    //WPSTYLE_CENTER 置中 0                    //WPSTYLE_TILE 平鋪 1                    //WPSTYLE_STRETCH 展開 2                     WPSTYLE dwstyle = WPSTYLE.STRETCH;//這裡調整顯示背景圖片樣式                    WALLPAPEROPT wp = new WALLPAPEROPT();                    wp.dwSize = System.Runtime.InteropServices.Marshal.SizeOf(wp);                    wp.dwStyle = dwstyle;                    iad.SetWallpaperOptions(ref wp, 0);                    iad.SetWallpaper(filename, 0);                    iad.ApplyChanges(AD_APPLY.ALL);                    System.Runtime.InteropServices.Marshal.ReleaseComObject(ad);                    ad = null;                }                return true;            }            catch            {                return false;            }        }