IE9 in IE7-mode: document.body is not yet defined when scrollLeft is called

[acutus]

For IE9 running in IE7 mode (in an embedded WebBrowser component in a WPF-application) The document.body doesn't seem to be necessarily initialized when the following function is called, resulting in an error saying that : "unable to get value of the property 'scrollLeft' object is null or undefined".

function MouseMove() {
    document.body.scrollLeft;
    document.body.scrollTop;
}

(The little bit of magic in jsxgraph.js, lines 95-98 :) )

This can be avoided just by adding a simple "if(document.body){ ... }" check.

This rather exotic case (IE9 in IE7 mode within a WPF WebBrowser-control, !DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN") is currently the only tested one.

[migerh]

Thanks for this detailed report. I rebuilt jsxgraph, if you want you can find it here and try it:

http://jsxgraph.uni-bayreuth.de/~michael/jsxgraph-nightly/2012-12-03.1405/

I omitted a test for existence of document because in that case, supportsVML() should return false.

[acutus]

Whoa, that really was a quick reaction!

Took down the build and everything seems to be running smoothly in the same setup.

Thank you, really a pleasure to report when the reaction is this quick :).