database connection in asp.net

Do i need to write the code for database connection in each of  the .aspx page in the appln?

see i have a login.aspx,a home.aspx,and users.aspx;

 I write the code to connect to db in login.aspx.cs

can that connection object be used in other pages,or do i need to every time create the connection object  and write the whole code for db conn in all page?

Is it possible to make the conn object as a session variable?? Am not sure????

pls give an ans

 

 
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