For run-time applications, this merger is a merging of the CSS class names that will be rendered as part of the CSS class attribute. Therefore, at run-time the precedence of styles is resolved in accordance with the Cascading Style Sheet recommendation (in particular, a CSS class defined later in the document supercedes one defined earlier when both CSS classes are named in the same class attribute). The order of how styles get appended is inconsequential at run-time.
Before AppendStyle can be called, the SmartRenderer must be initialized on the UI elements' scene graph. AppendStyle returns the primary style, style1, unchanged when this prerequisite isn't met.
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2