For Each dto As ProductDto In ProductDtoList
                If IsNothing(dto.materialTextureName) = False Then
                    Dim optionDto As OptionDto = New OptionDto(dto.materialTextureId, dto.materialTextureName)
                    Dim a = New Predicate(Of OptionDto)(Function(c)
                                                            Return optionDto.id = c.id
                                                        End Function)
                    If listdto.Exists(a) Then
                        Exit For
                    End If
                    listdto.Add(optionDto)
                End If
            Next