SessionExtensions.vb

Public Module SessionExtensions

    <Runtime.CompilerServices.Extension()>
    Public Function TryGetValue(session As System.Web.SessionState.HttpSessionState,
                                sessionItemName As String,
                                ByRef result As Object) As Boolean

        If session Is Nothing Then
            Throw New ArgumentNullException("Session", "Session is nothing.")
        End If
        If String.IsNullOrEmpty(sessionItemName) Then
            Throw New ArgumentException("SessionItemName is nothing or empty.", "SessionItemName")
        End If

        result = session(sessionItemName)

        Return result IsNot Nothing

    End Function

    <Extension()>
    Public Function TryConvertValueOf(Of T As {Class})(ByVal sess As HttpSessionState, 
                                                       ByVal param As String, 
                                                       ByRef output As T) As Boolean
        Dim obj As Object = sess(param)
        If TypeOf obj Is T Then
            output = DirectCast(obj, T)
            Return output IsNot Nothing
        End If
        Return False
    End Function

End Module