Set filename of Excel sheet to export from html table

Question

I have one html table. Now I am exporting this table to Excel Sheet 

using Javascript. When this excel sheet is getting downloaded,the

filename is like "download.xls". Now I want filename as current_date

instead of "download"...Below is my javascript code:

 

function write_to_excel() {

var tab_text = "<table border='2px'><tr>";

var textRange; var j = 0;

tab = document.getElementById('tt1'); // id of table

tab1 = document.getElementById('testTable'); // id of table

for (i = 0; i < tab.rows.length; i++) {

tab_text = tab_text + tab.rows[i].innerHTML + "</tr>";

//tab_text=tab_text+"</tr>";

}

for (j = 0; j < tab1.rows.length; j++) {

tab_text = tab_text + tab1.rows[j].innerHTML + "</tr>";

//tab_text=tab_text+"</tr>";

}

tab_text = tab_text + "</table>";

tab_text = tab_text.replace(/<A[^>]*>|<\/A>/g, ""); //remove if u want links in your table

tab_text = tab_text.replace(/<img[^>]*>/gi, ""); // remove if u want images in your table

tab_text = tab_text.replace(/<input[^>]*>|<\/input>/gi, ""); // reomves input params

//var a = document.createElement('a');

var ua = window.navigator.userAgent;

var msie = ua.indexOf("MSIE ");

if (msie > 0 || !!navigator.userAgent.match(/Trident.*rv\:11\./)) // If Internet Explorer

{

txtArea1.document.open("txt/html", "replace");

txtArea1.document.write(tab_text);

txtArea1.document.close();

txtArea1.focus();

sa = txtArea1.document.execCommand("SaveAs", true, "Say Thanks to Sumit.xls");

}

else //other browser not tested on IE 11

sa = window.open('data:application/vnd.ms-excel,' + encodeURIComponent(tab_text));

return (sa);

}