使用Blob.js实现Excel导出

/* eslint-disable */
/*  Blob.js
 * A Blob implementation.
 * 2014-05-27
 *
 * By Eli Grey, http://eligrey.com
 * By Devin Samarin, https://github.com/eboyjr
 * License: X11/MIT
 *   See LICENSE.md
 */

/*global self, unescape */
/*jslint bitwise: true, regexp: true, confusion: true, es5: true, vars: true, white: true,
 plusplus: true */

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

(function (view) {
  "use strict";

  view.URL = view.URL || view.webkitURL;

  if (view.Blob && view.URL) {
      try {
          new Blob;
          return;
      } catch (e) {}
  }

  // Internally we use a BlobBuilder implementation to base Blob off of

  // in order to support older browsers that only have BlobBuilder
  var BlobBuilder = view.BlobBuilder || view.WebKitBlobBuilder || view.MozBlobBuilder || (function(view) {
          var
              get_class = function(object) {
                  return Object.prototype.toString.call(object).match(/^\[object\s(.*)\]$/)[1];
              }
              , FakeBlobBuilder = function BlobBuilder() {
                  this.data = [];
              }
              , FakeBlob = function Blob(data, type, encoding) {
                  this.data = data;
                  this.size = data.length;
                  this.type = type;
                  this.encoding = encoding;
              }
              , FBB_proto = FakeBlobBuilder.prototype
              , FB_proto = FakeBlob.prototype
              , FileReaderSync = view.FileReaderSync
              , FileException = function(type) {
                  this.code = this[this.name = type];
              }
              , file_ex_codes = (
                  "NOT_FOUND_ERR SECURITY_ERR ABORT_ERR NOT_READABLE_ERR ENCODING_ERR "
                  + "NO_MODIFICATION_ALLOWED_ERR INVALID_STATE_ERR SYNTAX_ERR"
              ).split(" ")
              , file_ex_code = file_ex_codes.length
              , real_URL = view.URL || view.webkitURL || view
              , real_create_object_URL = real_URL.createObjectURL
              , real_revoke_object_URL = real_URL.revokeObjectURL
              , URL = real_URL