Cannot create unknown type 'Style' Exception in WPF?
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I have this code to create dynamic button style based on generated points from another class which generates on runtime and i have this exception 
'Cannot create unknown type 'Style'.' Line number '1' and line position '2'.

    string s = "<Style xmlns:x=\"http://schemas.microsoft.com/winfx/2006/xaml\" x:Key=\"Mystyle\" TargetType=\"Button\">" +
            "<Setter Property=\"Template\">" +
                "<Setter.Value>" +
                  "  <ControlTemplate TargetType=\"{x:Type Button}\">" +
                       " <Grid >" +
                               " <Polygon  Points=\""+points+" Fill=\"{TemplateBinding Background}\"" +
                             "Stroke=\"{TemplateBinding BorderBrush}\" DataContext=\"{Binding}\" />" +
                           " <ContentPresenter HorizontalAlignment=\"Center\"" +
                                       "   VerticalAlignment=\"Center\"/>" +
                       " </Grid>" +
                  "  </ControlTemplate>" +
               " </Setter.Value>" +
        "    </Setter>" +
       " </Style>";
            StringReader stringReader = new StringReader(s);
            XmlReader xmlReader = XmlReader.Create(stringReader);
            Style  readerLoadButton = (Style)XamlReader.Load(xmlReader);