[Dojo-interest] global variable value not retained within load function

Mon Feb 5 08:47:45 MST 2007

Could you paste your entire page?  It's difficult to tell if you have a 
scoping issue or a timing issue.

Remember that in-line JavaScript is executed as the page is parsed 
top-to-bottom, and /then/ any onload functionality will be executed ... 
so if you're initializing trunkGroup inside dojo.addOnLoad(...), that 
initialization would not happen until after your document.write(...) 
call below.

<body>
<script language="javascript">
document.write(trunkGroup[0]);  // outputs "undefined"
</script>
</body>

I can tell you that the following executes "array" "string" "string", 
showing that you can indeed manipulate global variables in more-specific 
scopes.

var bip = "array";

function bip2 () {
  this.bip3 = function() {
    bip = "string";
    alert(bip);
  }
};

dojo.addOnLoad(
    function() {
      alert(bip);
      new bip2().bip3();
      alert(bip);
    }
  );

One final note, using "var" declares that variable specifically to its 
containing scope.  So if you're doing:
dojo.addOnLoad(
    function() {
      var trunkGroup ...
    });

... then "trunkGroup" is not going to be global, but a private 
member-variable of the anonymous class you're passing into the addOnload 
function.

-- Jim

Meng-Shyang Teng wrote:
> Within the load function, I have the following:
>
> var trunkGroup = new Array();  // global variable defined here
> function getTrunkGroups() {
> .. // some code omitted here
>
> var bindArgs = {
> load: function(type, data, evt){
>  trunkGroup = eval(data);  // output correct value
>  alert (trunkGroup[0]);
>   }
> }
> ..
> }
>
>
> I am attempting to assign a global variable trunkGroup.  Although the 
> alert(trunkGroup[0]) does return correct values, the trunkGroup is no 
> longer defined within the html document.  Is there a way to assign a 
> global variable inside of the load function?
>
> I have the following code inside of my html:
>
> <body>
> <script language="javascript">
> document.write(trunkGroup[0]);  // outputs "undefined"
> </script>
> </body>
> ------------------------------------------------------------------------
>
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