If you mean URL rewriting, you can use the following solutions : first using UrlMapping configuration in web.config file
<urlMappings enabled="true">
<add url="~/Test.aspx" mappedUrl="~/Default.aspx?Code=0" />
<add url="~/Test1.aspx" mappedUrl="~/Default.aspx?Code=1" />
</urlMappings>
and the other way could be using RouteCollection.MapPageRoute method in application_Start event in global.asax class
for more information you can visit the following pages :
http://www.4guysfromrolla.com/articles/012710-1.aspx[
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http://msdn.microsoft.com/en-us/library/vstudio/ms228302(v=vs.100).aspx[
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