CKEditor: Text box in link dialog

Question

I'm trying to interact with a text box in the Link dialog (get the value and set the value). Started with what's already there but it's not working...

CKEDITOR.dialog.add('link', function (a)
{ 
    var b = function () 
    {
         var s = this.getDialog(),
         z = s.getContentElement('info', 'txtUrl');
         z.setValue('asdasd');
    });
});

Any ideas will be helpful as I'm sure I'm almost there!

R