[inkedmn]

the easiest way would be something like:

if(pageindex % 2 == 0)
    // then it's even
else
    // then it's odd

the modulus operator (%) returns the remainder of any division operation. Here's a python example (since it's easier to read/understand)

>>> 3 % 2
1
>>> 14 % 7
0

because 14 divides evenly by 7, there's no remainder, but 3 doesn't divide evenly by 2, so there's a remainder of 1, etc.

hth