JSFiddle - React, Tailwind, and code Playground

HTML

<form enctype="multipart/form-data">
  <input id="upload" type=file name="files[]">
</form>

<textarea class="form-control" rows=35 cols=120 id="xlx_json"></textarea>



<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/xlsx/0.8.0/jszip.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/xlsx/0.8.0/xlsx.js"></script>
<script>
  document.getElementById('upload').addEventListener('change', handleFileSelect, false);
  var ExcelToJSON = function() {

    this.parseExcel = function(file) {
      var reader = new FileReader();

      reader.onload = function(e) {
        var data = e.target.result;
        var workbook = XLSX.read(data, {
          type: 'binary'
        });
        workbook.SheetNames.forEach(function(sheetName) {
          // Here is your object
          var XL_row_object = XLSX.utils.sheet_to_row_object_array(workbook.Sheets[sheetName]);
          var json_object = JSON.stringify(XL_row_object);
          console.log(JSON.parse(json_object));
          jQuery('#xlx_json').val(json_object);
        })
      };

      reader.onerror = function(ex) {
        console.log(ex);
      };

      reader.readAsBinaryString(file);
    };
  };

  function handleFileSelect(evt) {

    var files = evt.target.files; // FileList object
    var xl2json = new ExcelToJSON();
    xl2json.parseExcel(files[0]);
  }
</script>