Dynamics CRM online javascript - dealing with HTML web resource and executing jscript

What is the appropriate way to, for lack of a better term, get inside of an HTML web resource to execute javascript? I currently use this line -

Xrm.Page.getControl("WebResource_myWebResouce").getObject().contentWindow.window.myFunc();

Generally, myFunc() goes and does something like retrieves data and builds a table, etc. I'm finding that my way of doing it is sometimes buggy/doesn't work all the time. There is a lot online about this topic, but much of it is sort of dated at this point. I believe I'm doing something slightly off here. Is there is a consistent, best practice way to handle this? Thanks.