Active Directory登陆认证

    Private Function ValidateActiveDirectoryLogin(ByVal Domain As String, ByVal Username As String, ByVal Password As String) As Boolean
        Dim Success As Boolean = False
        Dim Entry As New System.DirectoryServices.DirectoryEntry("LDAP://" & Domain, Username, Password)
        Dim Searcher As New System.DirectoryServices.DirectorySearcher(Entry)
        Searcher.SearchScope = DirectoryServices.SearchScope.Subtree
        Try
            Dim Results As System.DirectoryServices.SearchResult = Searcher.FindOne
            Success = Not (Results Is Nothing)
        Catch
            Success = False
        End Try
        Return Success

    End Function