Web Worker 调用Ajax

 var document = self.document = {parentNode: null, nodeType: 9, toString: function() {return "FakeDocument"}};var window = self.window = self;var fakeElement = Object.create(document);
 
fakeElement.nodeType = 1;
 
fakeElement.toString=function() {return "FakeElement"};
 
fakeElement.parentNode = fakeElement.firstChild = fakeElement.lastChild = fakeElement;
 
fakeElement.ownerDocument = document;
 
document.head = document.body = fakeElement;
 
document.ownerDocument = document.documentElement = document;
 
document.getElementById = document.createElement = function() {return fakeElement;};
 
document.createDocumentFragment = function() {return this;};
 
document.getElementsByTagName = document.getElementsByClassName = function() {return [fakeElement];};
 
document.getAttribute = document.setAttribute = document.removeChild =
 
document.addEventListener = document.removeEventListener =
 
function() {return null;};
 
document.cloneNode = document.appendChild = function() {return this;};
 
document.appendChild = function(child) {return child;};