Question

I must have used someone’s existing code as a framework, and I developed a jQuery/JavaScript application I now need to use. It works fine if invoked from within the following code but I need to pass values for nnn from elsewhere in the page. Because I don’t understand jQuery structure well enough, my efforts so far have failed.

<script>
$(function() {
.
.
.
  var BuildTree = function(centralID) {
    ...
  }
  BuildTree(nnn);
});

I want to do something like:

function BuildTree(...) {
...
}

Thanks!

Answer 1

You have a problem with scope, you’re defining BuildTree inside the scope of the function you’re passing to jQuery (or $ in this case).

This is a problem in terms of javascript and no jQuery, functions define a scope, what it means is that what you define inside a funcion lives inside of it.

function test() {
    var variable = 2;    //variable within the scope of test
}
variable //undefined

So, if you need to use it outside, you could define it outside the function and then use it inside or do something like:

$(function(){
...
    window.BuildTree = BuildTree //global scope
...
});

Also be careful with the caps, it means you’re defining a Constructor, by javascript standars