windows Application with sql server

Question

i had label box as "user id"
another label as "name"  
another label as "phone number"   totally 3 labels are there. 

         and  at the same time i have database as "Detail"
in that i have only there are three fields   user id , name , phone number.
 
   

User Id	Name	Phone number

  here, I need to get auto user id when i am  going add new one. it need to store auto user id  and  i am only give two inputs to store in the database they are name and phone numbers.


that is windows application connected with database.input in the window application it need to update in the database.

My Question is how to get the auto user id?