Prevent missing file/object from stopping code.

Question

How do I prevent assigning of an object that doesn't exist to a variable from stopping the script?  For example, I want to assign the application 800x600.psd to a variable, if it's open, so that the program can make use of it, but if it's not open, I don't want the script to stop on the error that it could not find it.  The code I use to assign this file to a variable is:
var theScaledDoc = app.documents.getByName("800x600.psd");
But if I run this without that file currently open in Photoshop, it stops the script with the error "No such element".  How do I bypass this error if the file is not open, yet assign it if it is open?
Thanks for any help!
dgolberg

Answer 1

You could trap the error and open the file if required ie:-
function main(){
try{
   var theScaledDoc = app.documents.getByName("800x600.psd");
   }catch(e){
       if (confirm('The file is not open. Would you like to open it?')) {
           var theScaledDoc = File.openDialog("Please select Image","*.*");
           open(theScaledDoc );
           }else{
               return;
main();