Fusion chart javascript funcyion not work

<script type="text/javascript" language="javascript">
       var initiateExport = false;

       function exportCharts(exportFormat) {
           initiateExport = true;
           for (var chartRef in FusionCharts.items) {  ///// This line not execute properly

               if (FusionCharts.items[chartRef].exportChart) {
                   document.getElementById("linkToExportedFile4").innerHTML = "";
                   document.getElementById("Div1").innerHTML = "";
                   FusionCharts.items[chartRef].exportChart({ "exportFormat": exportFormat });

               }
               else {

                   document.getElementById("linkToExportedFile4").innerHTML = "Please wait till the chart completes rendering...";
                   document.getElementById("Div1").innerHTML = "Please wait till the chart completes rendering...";

               }
           }
       }

       function FC_Exported(statusObj) {
           if (initiateExport) {
               initiateExport = false;
               document.getElementById('<%=txtstatone.ClientID%>').value = "";
           }

           if (statusObj.statusCode == "1") {

               document.getElementById('<%=txtstatone.ClientID%>').value += statusObj.fileName;

               document.getElementById("linkToExportedFile4").innerHTML += "Export successful. View it from <a target='_blank'  href='" + statusObj.fileName + "'>Here</a>.<br/>";

               document.getElementById("Div1").innerHTML += "Attched <a target='_blank' id='showclik' onclick='JavaScript:show()' href='" + statusObj.fileName + "'>PDF</a>.<br>";

           }
           else {
               document.getElementById("linkToExportedFile4").innerHTML += "Export unsuccessful. Notice from export handler :" + statusObj.notice + "<br/>";
               document.getElementById("Div1").innerHTML += "Export unsuccessful. Notice from export handler :" + statusObj.notice + "<br/>";

           }
       }

   </script>