不使用let， 使用var

js/index.js

 $(function () {
-  let loadHtmlArr = [
+  var loadHtmlArr = [
     // "cover",
     // // "catalog",
     // "preface",

js/preface.js

 $(function() {
   // outerHeight(true) 高度为 height+margin+padding+border
-  let parameter = $(".preface_html_root").data("page-params");
+  var parameter = $(".preface_html_root").data("page-params");
   console.log("preface:parameter", parameter);
 });

js/section_1.js

 $(function() {
   // outerHeight(true) 高度为 height+margin+padding+border
-  let parameter = $(".section_1_html_root").data("page-params");
+  var parameter = $(".section_1_html_root").data("page-params");
   console.log("section_1:parameter", parameter);
 });

js/section_2.js

 $(function() {
   // outerHeight(true) 高度为 height+margin+padding+border
-  let parameter = $(".section_2_html_root").data("page-params");
+  var parameter = $(".section_2_html_root").data("page-params");
   console.log("section_2:parameter", parameter);
 });

js/section_3.js

 function initSubjectBadEcharts() {
-  let xAxis_data = [
+  var xAxis_data = [
     "语文",
     "数学",
     "英语",
     "历史",
     "生物"
   ];
-  let series_data = [12, 20, 15, 8, 7, 11, 13,  15, 8];
-  let option = {
+  var series_data = [12, 20, 15, 8, 7, 11, 13,  15, 8];
+  var option = {
     animation: false,
     title: {
       text: "人",
       },
     ],
   };
-  let myEcharts = echarts.init(document.querySelector(".section_3 #subjectBadEcharts"));
+  var myEcharts = echarts.init(document.querySelector(".section_3 #subjectBadEcharts"));
   myEcharts.clear();
   myEcharts.setOption(option);
 }
 $(function () {
   // outerHeight(true) 高度为 height+margin+padding+border
-  let parameter = $(".section_3_html_root").data("page-params");
+  var parameter = $(".section_3_html_root").data("page-params");
   console.log("section_3:parameter", parameter);
 
   initSubjectBadEcharts();

js/section_4.js

 function initSubjectGoodEcharts() {
-  let xAxis_data = [
+  var xAxis_data = [
     "语文",
     "数学",
     "英语",
     "历史",
     "生物"
   ];
-  let series_data = [12, 20, 15, 8, 7, 11, 13,  15, 8];
-  let option = {
+  var series_data = [12, 20, 15, 8, 7, 11, 13,  15, 8];
+  var option = {
     animation: false,
     title: {
       text: "人",
       },
     ],
   };
-  let myEcharts = echarts.init(document.querySelector(".section_4 #subjectGoodEcharts"));
+  var myEcharts = echarts.init(document.querySelector(".section_4 #subjectGoodEcharts"));
   myEcharts.clear();
   myEcharts.setOption(option);
 }
 $(function() {
   // outerHeight(true) 高度为 height+margin+padding+border
-  let parameter = $(".section_4_html_root").data("page-params");
+  var parameter = $(".section_4_html_root").data("page-params");
   console.log("section_4:parameter", parameter);
 
   initSubjectGoodEcharts();

librarys/utils/index.js

 jQuery.extend({
   UnitUtil: (function() {
-    let pxWidth = 0;
-    let tmpNode = document.createElement("DIV");
+    var pxWidth = 0;
+    var tmpNode = document.createElement("DIV");
     tmpNode.style.cssText =
       "width:1mm;position:absolute;left:0px;top:0px;z-index:99;visibility:hidden";
     document.body.appendChild(tmpNode);