使用IActiveDesktop对象的一些方法

先声明，看不懂VB的别在这里乱叫，烦。这里是给大家例子看的。不是帮你写代码让你COPY了就能用的。
Windows32使用的一些常量定义:

Public Class _win32 Public Const AD_APPLY_ALL As Integer = AD_APPLY_SAVE Or AD_APPLY_HTMLGEN Or AD_APPLY_REFRESH Public Const AD_APPLY_BUFFERED_REFRESH As Integer = &H10 Public Const AD_APPLY_DYNAMICREFRESH As Integer = &H20 Public Const AD_APPLY_FORCE As Integer = &H8 Public Const AD_APPLY_HTMLGEN As Integer = &H2 Public Const AD_APPLY_REFRESH As Integer = &H4 Public Const AD_APPLY_SAVE As Integer = &H1 Public Const COMP_ELEM_ALL As Integer = COMP_ELEM_TYPE Or COMP_ELEM_CHECKED Or COMP_ELEM_DIRTY Or COMP_ELEM_NOSCROLL Or COMP_ELEM_POS_LEFT Or COMP_ELEM_SIZE_WIDTH Or COMP_ELEM_SIZE_HEIGHT Or COMP_ELEM_POS_ZINDEX Or COMP_ELEM_SOURCE Or COMP_ELEM_FRIENDLYNAME Or COMP_ELEM_POS_TOP Or COMP_ELEM_SUBSCRIBEDURL Or COMP_ELEM_ORIGINAL_CSI Or COMP_ELEM_RESTORED_CSI Or COMP_ELEM_CURITEMSTATE Public Const COMP_ELEM_CHECKED As Integer = &H2 Public Const COMP_ELEM_CURITEMSTATE As Integer = &H4000 Public Const COMP_ELEM_DIRTY As Integer = &H4 Public Const COMP_ELEM_FRIENDLYNAME As Integer = &H400 Public Const COMP_ELEM_NOSCROLL As Integer = &H8 Public Const COMP_ELEM_ORIGINAL_CSI As Integer = &H1000 Public Const COMP_ELEM_POS_LEFT As Integer = &H10 Public Const COMP_ELEM_POS_TOP As Integer = &H20 Public Const COMP_ELEM_POS_ZINDEX As Integer = &H100 Public Const COMP_ELEM_RESTORED_CSI As Integer = &H2000 Public Const COMP_ELEM_SIZE_HEIGHT As Integer = &H80 Public Const COMP_ELEM_SIZE_WIDTH As Integer = &H40 Public Const COMP_ELEM_SOURCE As Integer = &H200 Public Const COMP_ELEM_TYPE As Integer = &H1 Public Const COMP_ELEM_SUBSCRIBEDURL As Integer = &H800 Public Const COMP_TYPE_CONTROL As Integer = 3 Public Const COMP_TYPE_HTMLDOC As Integer = 0 Public Const COMP_TYPE_PICTURE As Integer = 1 Public Const COMP_TYPE_WEBSITE As Integer = 2 Public Const COMPONENT_DEFAULT_LEFT As Integer = &HFFFF Public Const COMPONENT_DEFAULT_TOP As Integer = &HFFFF Public Const IS_FULLSCREEN As Integer = &H2 Public Const IS_NORMAL As Integer = &H1 Public Const IS_SPLIT As Integer = &H4 Public Const MAX_PATH As Integer = 260 Public Const WPSTYLE_CENTER As Integer = 0 Public Const WPSTYLE_MAX As Integer = 3 Public Const WPSTYLE_STRETCH As Integer = 2 Public Const WPSTYLE_TILE As Integer = 1 <StructLayout(LayoutKind.Sequential)> _ Public Structure _tagCOMPSTATEINFO Private dwSize As Integer Private iLeft As Integer Private iTop As Integer Private dwWidth As Integer Private dwHeight As Integer Private dwItemState As Integer End Structure <StructLayout(LayoutKind.Sequential)> _ Public Structure _tagCOMPPOS Private dwSize As Integer Private iLeft As Integer Private iTop As Integer Private dwWidth As Integer Private dwHeight As Integer Private izIndex As Integer <MarshalAs(UnmanagedType.Bool)> _ Private fCanResize As Boolean <MarshalAs(UnmanagedType.Bool)> _ Private fCanResizeX As Boolean <MarshalAs(UnmanagedType.Bool)> _ Private fCanResizeY As Boolean Private iPreferredLeftPercent As Integer Private iPreferredTopPercent As Integer End Structure <StructLayout(LayoutKind.Sequential)> _ Public Structure _tagCOMPONENT Public dwSize As Integer Public dwID As Integer Public iComponentType As Integer <MarshalAs(UnmanagedType.Bool)> _ Public fChecked As Boolean <MarshalAs(UnmanagedType.Bool)> _ Public fDirty As Boolean <MarshalAs(UnmanagedType.Bool)> _ Public fNoScroll As Boolean Public cpPos As _tagCOMPPOS <MarshalAs(UnmanagedType.ByValTStr, SizeConst:=MAX_PATH)> _ Public wszFriendlyName As String <MarshalAs(UnmanagedType.ByValTStr, SizeConst:=2084)> _ Public wszSource As String <MarshalAs(UnmanagedType.ByValTStr, SizeConst:=2084)> _ Public wszSubscribedURL As String Public dwCurItemState As Integer Public csiOriginal As _tagCOMPSTATEINFO Public csiRestored As _tagCOMPSTATEINFO End Structure <StructLayout(LayoutKind.Sequential)> _ Public Structure _tagCOMPONENTSOPT Public dwSize As Integer <MarshalAs(UnmanagedType.Bool)> _ Public fEnableComponents As Boolean <MarshalAs(UnmanagedType.Bool)> _ Public fActiveDesktop As Boolean End Structure <StructLayout(LayoutKind.Sequential)> _ Public Structure _tagWALLPAPEROPT Public dwSize As Integer Public dwStyle As Integer End Structure End Class

申明IActiveDesktop对象
<ComImport(), Guid("F490EB00-1240-11D1-9888-006097DEACF9"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)> _ Public Interface IActiveDesktop Function ApplyChanges(ByVal dwFlags As Integer) As IntPtr Function GetWallpaper(<MarshalAs(UnmanagedType.LPWStr)> ByVal pwszWallpaper As System.Text.StringBuilder, ByVal cchWallpaper As Integer, ByVal dwReserved As Integer) As IntPtr Function SetWallpaper(<MarshalAs(UnmanagedType.LPWStr)> ByVal pwszWallpaper As String, ByVal dwReserved As Integer) As IntPtr Function GetWallpaperOptions(ByRef pwpo As _win32._tagWALLPAPEROPT, ByVal dwReserved As Integer) As IntPtr Function SetWallpaperOptions(<[In]()> ByRef pwpo As _win32._tagWALLPAPEROPT, ByVal dwReserved As Integer) As IntPtr Function GetPattern(<MarshalAs(UnmanagedType.LPWStr)> ByVal pwszPattern As System.Text.StringBuilder, ByVal cchPattern As Integer, ByVal dwReserved As Integer) As IntPtr Function SetPattern(<MarshalAs(UnmanagedType.LPWStr)> ByVal pwszPattern As String, ByVal dwReserved As Integer) As IntPtr Function GetDesktopItemOptions(ByRef pco As _win32._tagCOMPONENTSOPT, ByVal dwReserved As Integer) As IntPtr Function SetDesktopItemOptions(<[In]()> ByRef pcomp As _win32._tagCOMPONENTSOPT, ByVal dwReserved As Integer) As IntPtr Function AddDesktopItem(<[In]()> ByRef pcomp As _win32._tagCOMPONENT, ByVal dwReserved As Integer) As IntPtr Function AddDesktopItemWithUI(ByVal hwnd As IntPtr, <[In]()> ByRef pcomp As _win32._tagCOMPONENT, ByVal dwFlags As Integer) As IntPtr Function ModifyDesktopItem(<[In]()> ByRef pcomp As _win32._tagCOMPONENT, ByVal dwFlags As Integer) As IntPtr Function RemoveDesktopItem(<[In]()> ByRef pcomp As _win32._tagCOMPONENT, ByVal dwReserved As Integer) As IntPtr Function GetDesktopItemCount(ByRef lpiCount As Integer, ByVal dwReserved As Integer) As IntPtr Function GetDesktopItem(ByVal nComponent As Integer, ByRef pcomp As _win32._tagCOMPONENT, ByVal dwReserved As Integer) As IntPtr Function GetDesktopItemByID(ByVal dwID As IntPtr, ByRef pcomp As _win32._tagCOMPONENT, ByVal dwReserved As Integer) As IntPtr Function GenerateDesktopItemHtml(<MarshalAs(UnmanagedType.LPWStr)> ByVal pwszFileName As String, <[In]()> ByRef pcomp As _win32._tagCOMPPOS, ByVal dwReserved As Integer) As IntPtr Function AddUrl(ByVal hwnd As IntPtr, <MarshalAs(UnmanagedType.LPWStr)> ByVal pszSource As String, <[In]()> ByRef pcomp As _win32._tagCOMPONENT, ByVal dwFlags As Integer) As IntPtr Function GetDesktopItemBySource(<MarshalAs(UnmanagedType.LPWStr)> ByVal pszSource As String, ByRef pcomp As _win32._tagCOMPONENT, ByVal dwReserved As Integer) As IntPtr End Interface

现在开始使用这个对象。在使用之前要用CoCreateObject来进行创建。

    <DllImport("OLE32.DLL")> _ Public Shared Function CoCreateInstance( _ ByRef ClassGuid As Guid, _ ByVal pUnkOuter As IntPtr, _ ByVal dwClsContext As Integer, _ ByRef InterfaceGuid As Guid, _ ByRef Result As IActiveDesktop) As IntPtr End Function
Private CLSID_ActiveDesktop As New Guid("75048700-EF1F-11D0-9888-006097DEACF9")
Private IID_IActiveDesktop As New Guid("F490EB00-1240-11D1-9888-006097DEACF9")

Private Const CLSCTX_INPROC_SERVER As Integer = 1
Private ActiveDesktop As IActiveDesktop
下面的语句就是用来创建IActiveDesktop对象的。 CoCreateInstance(CLSID_ActiveDesktop,IntPtr.Zero, CLSCTX_INPROC_SERVER,IID_IActiveDesktop, ActiveDesktop)



    释放该对象: Marshal.ReleaseComObject(ActiveDesktop)
这里的俩条语句是用来在桌面上保存图片的。
ActiveDesktop.SetWallpaper(PicturePathName, 0) ActiveDesktop.ApplyChanges(_win32.AD_APPLY_FORCE Or _win32.AD_APPLY_SAVE Or _win32.AD_APPLY_REFRESH)

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