Andrew Warner

Andrew,

> I am playing around with your importxml.js script and
> wanted to know the reason that importXML() "pushes"
> each newly created XMLHttpRequest object to the global
> array MWJ_ldD.  

The global array serves two purposes.

1. For older browsers like Opera 7.5- and Internet Explorer on Mac that use
the iframe, it is a reference to the individual iframe. The MWJ_checkXMLLoad
function then continually checks the contents of the array asynchronously to
see if any of the iframes have loaded. If so, it runs their handler
function.

2. For browsers that can natively import XML (Opera 7.6+, Safari 1.2+,
Internet Explorer 5+ and Mozilla/Firefox), the array stores a reference to
the individual XML importing objects. The array index is then used by the
onreadystatechange handler function to reference the object. In theory, I
could use the 'this' keyword instead for most handler functions, but as the
comment says, browsers do not all correctly create the reference in the
onreadystatechange handler function:
"note: in XML importing event handlers, 'this' refers to window"
This was simply a simple workaround for that problem (one of several
possibilities, such as using target and srcElement - but I already had the
array for use with iframes, so I decided to re-use it).


Mark 'Tarquin' Wilton-Jones - author of http://www.howtocreate.co.uk/