in sstab go backward from one tab to another

[karthiknpm]

in my vb form im using sstab.in this sstab i have 6 tabs and tab index start from 0 to 5.during runtime when i press tab

key it goes one tab to another.but if i press shift+tab key it goes 5 to 4,4 to 3 etc.. but it wont goes from 1 to 0 th tab

pls send me code for me.