Hi all,
I have a dnn login page, when I click on login button,I want to send username and password to
my user control(which is developed in vs2008 as a dnn module) to check the login authentication.
How to do that?

Regards,
Kevin.

Could you describe in more detail what you are trying to do? If you are simply trying to determine if the user is logged in, there are objects and methods available to you. Look at the UserInfo class.

I have a web application which is developed in VS2008. This application is currently running and clients are using now. I have to change this application to CMS. For that I have created a login page in dotnetnuke, now I want to check the username and password with database in the old application. For that what I did is,
when click a login button(html control), I will call a javascript and from javascript it will send the username and password to the next page as a query string. In next page I have added a my own dnn module for checking the login. when the next page is loading , in the module I will check the username and password in the databse. The problem is I am using the querystring to pass the values. Is this the correct way to do this?
How can I send the values to dnn module other than query string. please help me....

It probably would be better to build an Authentication Provider to do this.  It can be fairly simple.  Check Joe Brinkman's blog (at DotNetNuke.com) for a simple example.