Script seems to pause each time a value is commited

Question

I created a simple script for copying the values of line "EVEN" to line "i" inside a button
var i = event.target.name.charAt(event.target.name.length-1);
this.getField("OPE003."+i+".NOCIVIQUE").value = this.getField("OPE003.EVEN.NOCIVIQUE").value;
this.getField("OPE003."+i+".TYPE.RUE").value = this.getField("OPE003.EVEN.TYPE.RUE").value;
this.getField("OPE003."+i+".RUE").value = this.getField("OPE003.EVEN.RUE").value;
this.getField("OPE003."+i+".APP").value = this.getField("OPE003.EVEN.APP").value;
this.getField("OPE003."+i+".ARRONDISSEMENT").value = this.getField("OPE003.EVEN.ARR").value;
this.getField("OPE003."+i+".CP").value = this.getField("OPE003.EVEN.CP").value;
the strange behavior is that instead of copying all the values at the same time, it copies only the first field.  if I press again, it copies the second one, on so on.
I tryied my button in an earlier version of the same document and it works great.  Now I think the only difference between the earlier and new version is I introduced a bunch of keystroke and validation scripts testing regular expressions when entering data in some fields that are not even those listed above.  There is no error in the console window and every value is transfered one after the other if I press the button 6 times.
What line of code have I possibly introduced that can stop such a simple button from working?

Answer 1

All variables declared outside of a function or used without declaring them first have document-wide scope. Since your code apparently triggers code in a different field that used the same variable name, there was a conflict. Changing the variable names is one approach, but it can be difficult to manage and it is much better to explicitly limit the scope of variables to only what is necessary. Normally you'd do this by placing as much code as you can into document-level JavaScripts as functions that get called in field events. But another way to do this is to place the code in field events inside anonymous functions that call themselves when the field script is triggered, something like:
// Place the code in an anonymous function and call it when this script is triggered.
(function () {
    var i = event.target.name.charAt(event.target.name.length-1);
    this.getField("OPE003."+i+".NOCIVIQUE").value = this.getField("OPE003.EVEN.NOCIVIQUE").value;
    this.getField("OPE003."+i+".TYPE.RUE").value = this.getField("OPE003.EVEN.TYPE.RUE").value;
    this.getField("OPE003."+i+".RUE").value = this.getField("OPE003.EVEN.RUE").value;
    this.getField("OPE003."+i+".APP").value = this.getField("OPE003.EVEN.APP").value;
    this.getField("OPE003."+i+".ARRONDISSEMENT").value = this.getField("OPE003.EVEN.ARR").value;
    this.getField("OPE003."+i+".CP").value = this.getField("OPE003.EVEN.CP").value;
If any of this code causes a script in another field that uses the same variable name to get triggered, then there won't be any conflict since the scope of the variables is local to the functions they are declared in.
This is convenient if you don't want to bother creating a named function in a document JavaScript and is in a form that is easy to convert to a named function if you ever want to. The code inside the function will work unchanged, you just have to slightly modify the first and last lines.