How to cast a page

Hi,

I have a scneraio where i do Server.Transfer from multiple pages to same screen, say get.aspx. Every page where i use Server.Transfer has one common property value that i am passing to get.aspx.
Like

Pages having    Server.Transfer(get.aspx)
 a1.aspx   Property Value (CountryName)
 b1.aspx   Property Value (CountryName)
 c1.aspx   Property Value (CountryName)
 d1.aspx   Property Value (CountryName)


Page get.aspx
In this page we have Context.Handler to check from where the request is coming, and access the value CountryName. How do i achieve this?

Thanks

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