on page 245 task 3 the code : dim rbl as radiobuttonlist = directcast(source,radiobuttonlist)

this causes an error - name "source" is not declared

if i change this to rbl the if then statement will say - cannot contain null.... how can i get Around this ? isbn 0 - 7645 - 8807 - 9

Dim rbl As RadioButtonList = DirectCast(sender, RadioButtonList)

this will correct the problem ! ! - this is from the COMPLEATE section which i just downloaded , source is not a valid object because it doesnt exist, sender is the correct method !