我的这段代码，调试时正常，但在sever2016下onchange事件会失效，该怎么改？谢谢！

<script type="text/javascript">
   
    //在表格中添加新行
    $("#picNumberOK").click(function() {
      //获取选择的文件数量
      let picNumber = document.getElementById("picNumber").value;
      if (picNumber > 0)
      {
        $("#PhotoList tr:not(:first)").remove();//删除表头以下全部行
        
        for (let i = 1; i <= picNumber; i++)
        {
          let table=document.getElementById("PhotoList");
          let tr=document.createElement("tr");
          tr.height="150px"
          let col_1=document.createElement("td");
          col_1.align="center";
          col_1.innerHTML=i;
          let col_2=document.createElement("td");
          col_2.align="center";
          let col_3=document.createElement("td");
          col_3.align="center";
          let col_4=document.createElement("td");
          col_4.align="center";
          let col_5=document.createElement("td");
          col_5.align="center";
          col_5.innerHTML="<textarea name=\"explain\" style=\"width:98%;height:140px;border-style:none\" />";
          let col_6=document.createElement("td");
          col_6.align="center";
          col_6.innerHTML="<a class=\"selectfile\">选择图片<input type=\"file\" name=\"imgFile\" id=\"imgFile\" onchange=\"Get()\"></a>";
          table.appendChild(tr);
          tr.appendChild(col_1);
          tr.appendChild(col_2);
          tr.appendChild(col_3);
          tr.appendChild(col_4);
          tr.appendChild(col_5);
          tr.appendChild(col_6);
        };
      }else{
        alert("请输入图片数！");
      }
    });
    function Get() {
        alert("您已选择了文件！");
    };
    </script>