how to tag one user control into another user in wpf

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C#

WPF

Hi ,
I am created one application, It having one main window this should act as master page as web application , remaing all other user controls , here each user control window act as one page , these controls are binding one child grid in the main window , for that how to replace one user control another
example : I have one registration page user control,it having 5 controls first after completion registration and another user control will be replace same area like some ,registration page user control will going to hide can u guide me or send snippets