Multiple Database on same portal

I am working on a project where on the same portal people from different location will login, so they get connected to different database depending on the location they choose at the time of login. There will be a dropdown list during login, where user can choose the location



I use ASP.NET Login control, security/membership class.


So what is the best way to implement this, should i save different connection string in web.config and based on location choosen by user read them? I would also have to change LocalSqlServer connection string for login control, how do i do this dynamicaly?

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