Capturing the url and switching between secure and non secure dynamicly in code

What I want to do when a page loads is find out if it is http:// or https:// and then change it if needed..
So if my url was to look like this http://www.MyLatestApp.com/Dir1/Dir2/Dir3/Page.aspx?Id=88223#76391&Cview=up
But i really wanted it to be https:// +  www.MyLatestApp.com/Dir1/Dir2/Dir3/Page.aspx?Id=88223#76391&Cview=up
How can I easily change this in C# ??
 
Thsnk in advance.
 
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