Checking to see if files exist not working as expected.

Question

Hey, so I've set up a script that determines the artist playing on iTunes and sets the background image to a preselected picture of them. I want to expand this to allow different pictures of the artists, and after a few attempts, decided to use a time based system. However, some artists have 2 images (named Artist1.jpg and Artist2.jpg), whilst others only have one (Artist.jpg). I can get the scripting right for if all artists have 2 images, yet am having problems with the system determining if certain files exist.
who is the artist playing, and myNum is either 1 or 2, and changes based on the time, both set earlier in the script and verified to work.
set MultiWall to ("/Users/ethan/Pictures/Music Wallpaper/" & who & myNum & ".jpg")
set SingleWall to ("/Users/ethan/Pictures/Music Wallpaper/" & who & ".jpg")
tell application "System Events"
                   if not (exists MultiWall) then
                                                       tell application "Finder"
                                                                      set desktop picture to file SingleWall
                                                       end tell
                   else
                                                       tell application "Finder"
                                                                      set desktop picture to file MultiWall
                              end tell
                                        end if
end tell
I've tried many variations of this, from less variables to more, restructuring it and whatnot and it just isn't working for me. Thanks all.

Answer 1

If you are still having difficulties you may like to try this method:
set myPath to "/Users/neville/Desktop/test" & ".png"
if (do shell script "/bin/test -e '" & myPath & "'; echo $?") is "0" then
  tell application "Safari" to open myPath
end if
It should work if you copy and paste it.
Please note the combined single and double quotes. Don't put a space between them. You may not need the single quotes if you have control over the path. Most people would opt for 'quoted form of' but I prefer concise code.