Question : Change AD password via web

Hi experts, i have this situation, i need that users form Active Directory, can change their password via web.
Whenever we create a new user we assign himn with a password that not only he cant change but it never expires also.
What i want to do is to make a web (c#, vb, etc) that allow the user to enter and modify or renew his password, also i need that the system alert the user whenever the password is about to expire.
Gimme a hand PLEASE!!!!
Thank you ALL

Answer : Change AD password via web

File are sequential so unless the lines are FIXED WIDTH in length and you can calculate the byte offset of XXX line number, then your only option is to COUNT line by line one at a time or by reading in "chunks" and splitting on carriage return/line feed.  Either option still requires you to physically count the lines until you reach the target.