How to make a tree in WPF

I need to make a tree which datas are fetched from stored Procedure,the stored Procedures make the datas at the following model:
lvl fullPath
1 A
2 A.B
3 A.B.C
3 A.B.D
2 A.E
2 A.F
....

when I fetch the datas from stored Procedure,I need some class to deal with it and then binding with XAML,make the tree in presentation at the following model:

A
|--B
| |---C
| |---D
|---E
|---F
....

I thought it isn't a big deal.but I'm getting crazy.Can anybody help me. I need a sample.