Per istanziare una classe unica utilizzabile da tutti i controlli:

¦window.resources¦
¦lineargradientbrush key="Colore" colorinterpolationmode="ScRgbLinearInterpolation" mappingmode="RelativeToBoundingBox"¦
¦lineargradientbrush.gradientstops¦
¦gradientstop color="Gainsboro" offset="0"¦
¦gradientstop color="AliceBlue" offset="0.1"¦
¦gradientstop color="White" offset="0.5"¦
¦gradientstop color="AliceBlue" offset="0.9"¦
¦gradientstop color="Wheat" offset="1"¦
¦/gradientstop¦
¦/gradientstop¦
¦lineargradientbrush key="ColoreInizio" colorinterpolationmode="SRgbLinearInterpolation" mappingmode="RelativeToBoundingBox" spreadmethod="Repeat"¦
¦lineargradientbrush.gradientstops¦
¦gradientstop color="White" offset="0"¦
¦gradientstop color="Gainsboro" offset="0.5"¦
¦gradientstop color="WhiteSmoke" offset="0.6"¦
¦gradientstop color="AntiqueWhite" offset="0.7"¦
¦gradientstop color="WhiteSmoke" offset="0.8"¦
¦gradientstop color="Gainsboro" offset="0.9"¦
¦gradientstop color="White" offset="1"¦
¦/gradientstop¦
¦/gradientstop¦
¦/gradientstop¦
...
poi all'interno del controllo
...Background="{StaticResource ResourceKey=Colore}"...