我的Vista应用程序需要知道用户是"以管理员身份"(提升)还是以标准用户(非提升)启动它。如何在运行时检测到？

解决方案

下面的C ++函数可以做到这一点：

HRESULT GetElevationType( __out TOKEN_ELEVATION_TYPE * ptet );

/*
Parameters:

ptet
    [out] Pointer to a variable that receives the elevation type of the current process.

    The possible values are:

    TokenElevationTypeDefault - This value indicates that either UAC is disabled, 
        or the process is started by a standard user (not a member of the Administrators group).

    The following two values can be returned only if both the UAC is enabled
    and the user is a member of the Administrator's group:

    TokenElevationTypeFull - the process is running elevated. 

    TokenElevationTypeLimited - the process is not running elevated.

Return Values:

    If the function succeeds, the return value is S_OK. 
    If the function fails, the return value is E_FAIL. To get extended error information, call GetLastError().

Implementation:
*/

HRESULT GetElevationType( __out TOKEN_ELEVATION_TYPE * ptet )
{
    if ( !IsVista() )
        return E_FAIL;

    HRESULT hResult = E_FAIL; // assume an error occurred
    HANDLE hToken   = NULL;

    if ( !::OpenProcessToken( 
                ::GetCurrentProcess(), 
                TOKEN_QUERY, 
                &hToken ) )
    {
        return hResult;
    }

    DWORD dwReturnLength = 0;

    if ( ::GetTokenInformation(
                hToken,
                TokenElevationType,
                ptet,
                sizeof( *ptet ),
                &dwReturnLength ) )
    {
            ASSERT( dwReturnLength == sizeof( *ptet ) );
            hResult = S_OK;
    }

    ::CloseHandle( hToken );

    return hResult;
}

对于使用C＃的我们来说，在Windows SDK中，有一个" UACDemo"应用程序作为"跨技术示例"的一部分。他们使用以下方法查找当前用户是否是管理员：

private bool IsAdministrator
{
    get
    {
        WindowsIdentity wi = WindowsIdentity.GetCurrent();
        WindowsPrincipal wp = new WindowsPrincipal(wi);

        return wp.IsInRole(WindowsBuiltInRole.Administrator);
    }
}

(注意：我将原始代码重构为属性，而不是" if"语句)