Download File by JS

Download File by JS using FileSaver.JS

HTML

<a href="https://github.com/eligrey/FileSaver.js">FileSaver.js</a> <br>
<button onclick="downloadFile();">Download File</button>

JavaScript

function downloadFile(){
    var blob = new Blob(["Hello, world!"], {type: "text/plain;charset=utf-8"});
    saveAs(blob, "hello world.txt");
}

/* FileSaver.js
 *  A saveAs() FileSaver implementation.
 *  2014-05-27
 *
 *  By Eli Grey, http://eligrey.com
 *  License: X11/MIT
 *    See https://github.com/eligrey/FileSaver.js/blob/master/LICENSE.md
 */

/*global self */
/*jslint bitwise: true, indent: 4, laxbreak: true, laxcomma: true, smarttabs: true, plusplus: true */

/*! @source http://purl.eligrey.com/github/FileSaver.js/blob/master/FileSaver.js */

var saveAs = saveAs
  // IE 10+ (native saveAs)
  || (typeof navigator !== "undefined" &&
      navigator.msSaveOrOpenBlob && navigator.msSaveOrOpenBlob.bind(navigator))
  // Everyone else
  || (function(view) {
	"use strict";
	// IE <10 is explicitly unsupported
	if (typeof navigator !== "undefined" &&
	    /MSIE [1-9]\./.test(navigator.userAgent)) {
		return;
	}
	var
		  doc = view.document
		  // only get URL when necessary in case Blob.js hasn't overridden it yet
		, get_URL = function() {
			return view.URL || view.webkitURL || view;
		}
		, save_link = doc.createElementNS("http://www.w3.org/1999/xhtml", "a")
		, can_use_save_link = !view.externalHost && "download" in save_link
		, click = function(node) {
			var event = doc.createEvent("MouseEvents");
			event.initMouseEvent(
				"click", true, false, view, 0, 0, 0, 0, 0
				, false, false, false, false, 0, null
			);
			node.dispatchEvent(event);
		}
		, webkit_req_fs = view.webkitRequestFileSystem
		, req_fs = view.requestFileSystem || webkit_req_fs || view.mozRequestFileSystem
		, throw_outside = function(ex) {
			(view.setImmediate || view.setTimeout)(function() {
				throw ex;
			}, 0);
		}
		, force_saveable_type = "application/octet-stream"
		, fs_min_size = 0
		, deletion_queue = []
		, process_deletion_queue = function() {
			var i = deletion_queue.length;
			while (i--) {
				var file = deletion_queue[i];
				if (typeof file === "string") { // file...