Authenticating Users with ASP.NET AJAX
ASP.NET 2.0 provides built-in membership management capabilities that allow applications to log users into and out of a Web site with minimal coding. Simply run the aspnet_regsql.exe tool to add Microsoft's membership database into your chosen database server (otherwise, a SQL Server 2005 Express database will be used), add a few lines of configuration code in web.config to point to your database, drag on a few controls such as the Login and CreateUserWizard controls, and you're ready to go!
However, each time a user logs in to your application, a postback operation occurs which, in some situations, may not be desirable. In cases where you'd like to log users into a Web site without performing a complete postback of a page, you can use the ASP.NET AJAX authentication service instead.
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