Automated login on ASP.NET website with C#

I have to login with a username / password with a c# program with asp.net form.

I have already do that with HttpUtility on PHP website but how to do that with ASP.NET website ?

In ASP.NET, I must handle postback and so on... Any ideas ?

Thanks in advance

Best regards

UPDATE :

I have to privilegied access to this website. I have to login like any other visitor. I 开发者_JS百科don't know if it clarify enough the question

Daniel is right the ASP.NET MembershipProvider is what your looking for. Here is a nice walkthorough the ASP.NET Membership Provider.

It explains in details what to do to let people register/sign on/off.

Finally, I will use the watin library (http://watin.sourceforge.net/) wich is exactly what I needed.

Thanks for your answers

Look into the Membership Providers provided by ASP.NET