What is Page Type Builder
Page Type Builder maps classes to EPiServer page types. When an EPiServer CMS site start up and PageTypeBuilder.dll is in its bin folder Page Type Builder will scan the application domain for classes that defines page
types and create corresponding page types in the EPiServer database. When a page (a PageData object) is retrieved through EPiServer's DataFactory class Page Type Builder will intercept the method call and check if the page is of a page type that is defined
in code. If it is, Page Type Builder will swap out that object with an instance of the class.
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