Dynamik CRM JavaScript -Feld sichtbar

function TickerChange() {
   if(Xrm.Page.getAttribute("tickersymbol").getValue() == null) {
       Xrm.Page.getControl("fax").setVisible(false);
   }
   else {
       Xrm.Page.getControl("fax").setVisible(true);
   }
}
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