about treeview,

[C# Programming]

hi everyone,i'm a beginner,this is my question;
make DATA show on treeview Automatically
for exeample
Field "class1" and "class2" is in Database "STUDENT"
a?b?c?d,four students are Belong to class1
e?f?g?h,four students are Belong to class2
class1 and class2 as father node
8 students as son node of each father node
how could it show on treeview Automatically?
and when click every student it will Trigger some Matter
please show me the code
Grateful for everyone!