JSFiddle - React, Tailwind, and code Playground

HTML

<body>
  <a>
    <button type="button" class="btn btn-default" title='Export Excel' onclick="export_Excel()">Download CSV</button>
  </a>
</body>

JavaScript

var result_table = [
										["Day", "Month", "Year"],
                    ["1", "January", "2016"], 
                    ["2", "February", "2016"],
                    ["3", "March", "2016"],
                    ["4", "April", "2016"],
                   ];


function export_Excel() {
    var lineArray = [];
    result_table.forEach(function (infoArray, index) {
       var line = infoArray.join(",");
       lineArray.push(index == 0 ? line : line);
    });
    var csvContent = lineArray.join("\n");
    var excel_file = document.createElement('a');
    excel_file.setAttribute('href', 'data:text/csv;charset=utf-8,' + encodeURIComponent(csvContent));
    excel_file.setAttribute('download', 'example.csv');
    document.body.appendChild(excel_file);
    excel_file.click();
    document.body.removeChild(excel_file);
}