How to create new users for sharepoint FBA application using application pages in visual studio 2010

I have successfully configured FBA for my sharepoint application. So i want to create new user from sharepoint site so that they can login & see their profiles. I found webpart solutions from Here but i want to create by myself. So how can i do this?

My another ouestion is once i create users then my users need to chane their password as well as what if they forget their password. So i need to create those webparts or application pages in visual studio.

So can anyone tell me how can i do all this stuff? Thanks in advance.

Assuming that you are talking about SQL based FBA. Implementing these solutions is matter of calling appropriate API in SqlMembershipProvider class of System.Web.Security.

For ex, for change password, see this function:

http://msdn.microsoft.com/en-us/library/system.web.security.sqlmembershipprovider.changepassword.aspx

Similarly, you would many functions in SqlRoleProvider class:
http://msdn.microsoft.com/en-us/library/system.web.security.sqlroleprovider.aspx