Can I use an IS function with Vlookup

[JJ in LA]

I am trying to write a formula that says If the Vlookup returns NA, then plus
a particular cell, otherwise return the vlookup value. Can this be done.
I've writen it as IF(isna(vlookup,etc.),+a1,(vlookup,etc)

Any Ideas as to why it dosen't work.

 

[Gary''s Student]

Remember the FALSE in VLOOKUP():

In A1 thru B3:

1 rover
2 queeny
3 mickey

and in C1:

2

Then =IF(ISNA(VLOOKUP(C1,A1:B3,2,FALSE)),A1,VLOOKUP(C1,A1:B3,2))
returns queeny, but put 22 in C1 and the same formula returns 1

 

[Dave Peterson]

In both vlookup() terms, too!

Remember the FALSE in VLOOKUP():

In A1 thru B3:

1 rover
2 queeny
3 mickey

and in C1:

2

Then =IF(ISNA(VLOOKUP(C1,A1:B3,2,FALSE)),A1,VLOOKUP(C1,A1:B3,2))
returns queeny, but put 22 in C1 and the same formula returns 1