I am sure this should be easy but I ahve been going crazy trying to get it to work:
return '<img border="0" src="'.$args['Image URL'].'?amount='.$args['invoiceAmount'].'&trans_id='.$args['invoiceNumber'].'&jrox_svalue_1=Sitename:javascript:document.write (sitename);" width="1" height="1">';
Essentially I need to inject the javascript varialbe "sitename" into the querystring value (jrox_svalue_1)for the image.
jrox_svalue_1=Sitename:javascript:document.write (sitename);
Any help would be apprecaited.