随意更改桌面壁纸
1． 的stdafx可的＃i nclude <afxwin.h>下加入
＃i nclude <wininet.h> // 必须在此位置加上则IActiveDesktop将找不到定义
2．在定义文件中加入＃i nclude <shlobj.h> // IActiveDesktop
3．只有在安装了IE4.0及以上版本时才能应用IActiveDesktop接口，只有active desktop（活动桌面）在打开的情况下才能应用SetWallpaper函数，所以先定义打开或关闭活动桌面的方法如下：
BOOL EnableActiveDesktop(BOOL bEnable)
{
// bEnable 为TRUE则打开，反之
HRESULT hr;
IActiveDesktop* pIADesk;
//创建接口的实例
hr = CoCreateInstance ( CLSID_ActiveDesktop, NULL, CLSCTX_INPROC_SERVER,
IID_IActiveDesktop, (void**) & pIADesk );
If ( !SUCCEEDED(hr) )
return FALSE;
COMPONENTSOPT comp;
comp.dwSize = sizeof(comp);
comp.fEnableComponents = bEnable;
//启用或关闭active desktop
comp.fActiveDesktop = bEnable;
hr = pIADesk ->SetDesktopItemOptions(&comp, 0);
if ( !SUCCEEDED(hr) )
return FALSE;
//释放接口的实例
pIADesk ->Release;
return TRUE;
}
4．当活动桌面开启后即可进行壁纸设置，代码如下：
//strPicFile是图像文件名,支持BMP JPEG GIF等格式
//dwStyle是墙纸的样式
//WPSTYLE_CENTER 居中 0
//WPSTYLE_TILE 平铺 1
//WPSTYLE_STRETCH 拉伸 2
//WPSTYLE_MAX 3
//返回值是TRUE时墙纸设置成功，返回FALSE时失败
BOOL SetWallpaper(CString &strPicFile, DWORD dwStyle)
{
HRESULT hr;
IActiveDesktop* pIAD;
//创建接口的实例
hr = CoCreateInstance ( CLSID_ActiveDesktop, NULL, CLSCTX_INPROC_SERVER,
IID_IActiveDesktop, (void**) &pIAD );
If ( !SUCCEEDED(hr) )
return FALSE;
//将文件名改为宽字符串,这是IActiveDesktop::SetWallpaper的要求
WCHAR wszWallpaper [MAX_PATH];
LPTSTR lpStr = strPicFile.GetBuffer(strPicFile.GetLength() );
MultiByteToWideChar(CP_ACP, 0, lpStr, -1, wszWallpaper, MAX_PATH);
strPicFile.ReleaseBuffer();
//设置墙纸
hr = pIAD->SetWallpaper(wszWallpaper, 0);
if(!SUCCEEDED(hr)) return FALSE;
//设置墙纸的样式
WALLPAPEROPT wpo;
wpo.dwSize = sizeof(wpo);
wpo.dwStyle = dwStyle;
hr = pIAD->SetWallpaperOptions(&wpo, 0);
if ( !SUCCEEDED(hr) )
return FALSE;
//应用墙纸的设置
hr = pIAD->ApplyChanges(AD_APPLY_ALL);
if ( !SUCCEEDED(hr) )
return FALSE;
//读取墙纸的文件名并打印在debug窗口内
hr = pIAD->GetWallpaper(wszWallpaper, MAX_PATH, 0);
CString strFile = wszWallpaper;
TRACE(strFile);
pIAD->Release();
return TRUE;
}