function startRequest(){
  var ifr = document.createElement('iframe');
  ifr.style.display = 'none';
  ifr.src = 'http://www.cnblogs.com/lab/cscript/cs2.html#paramdo';
  document.body.appendChild(ifr);
}

function checkHash() {
  try {
    var data = location.hash ? location.hash.substring(1) : '';
    if (console.log) {
      console.log('Now the data is '+data);
    }
  } catch(e) {};
}
setInterval(checkHash, 2000);

//模擬一個(gè)簡單的參數(shù)處理操作
switch(location.hash){
  case '#paramdo':
    callBack();
    break;
  case '#paramset':
    //do something……
    break;
}

function callBack(){
  try {
    parent.location.hash = 'somedata';
  } catch (e) {
    // ie、chrome的安全機(jī)制無法修改parent.location.hash，
    // 所以要利用一個(gè)中間的cnblogs域下的代理iframe
    var ifrproxy = document.createElement('iframe');
    ifrproxy.style.display = 'none';
    ifrproxy.src = 'http://a.com/test/cscript/cs3.html#somedata';  // 注意該文件在"a.com"域下
    document.body.appendChild(ifrproxy);
  }
}

//因?yàn)閜arent.parent和自身屬于同一個(gè)域，所以可以改變其location.hash的值
parent.parent.location.hash = self.location.hash.substring(1);

<script type="text/javascript">
  window.name = 'I was there!';  // 這里是要傳輸?shù)臄?shù)據(jù)，大小一般為2M，IE和firefox下可以大至32M左右
                   // 數(shù)據(jù)格式可以自定義，如json、字符串
</script>

<script type="text/javascript">
  var state = 0, 
  iframe = document.createElement('iframe'),
  loadfn = function() {
    if (state === 1) {
      var data = iframe.contentWindow.name;  // 讀取數(shù)據(jù)
      alert(data);  //彈出'I was there!'
    } else if (state === 0) {
      state = 1;
      iframe.contentWindow.location = "http://a.com/proxy.html";  // 設(shè)置的代理文件
    } 
  };
  iframe.src = 'http://b.com/data.html';
  if (iframe.attachEvent) {
    iframe.attachEvent('onload', loadfn);
  } else {
    iframe.onload = loadfn;
  }
  document.body.appendChild(iframe);
</script>

<script type="text/javascript">
  iframe.contentWindow.document.write('');
  iframe.contentWindow.close();
  document.body.removeChild(iframe);
</script>

<iframe id="ifr" src="b.com/index.html"></iframe>
<script type="text/javascript">
window.onload = function() {
  var ifr = document.getElementById('ifr');
  var targetOrigin = 'http://b.com'; // 若寫成'http://b.com/c/proxy.html'效果一樣
                    // 若寫成'http://c.com'就不會(huì)執(zhí)行postMessage了
  ifr.contentWindow.postMessage('I was there!', targetOrigin);
};
</script>

<script type="text/javascript">
  window.addEventListener('message', function(event){
    // 通過origin屬性判斷消息來源地址
    if (event.origin == 'http://a.com') {
      alert(event.data);  // 彈出"I was there!"
      alert(event.source); // 對a.com、index.html中window對象的引用
                 // 但由于同源策略，這里event.source不可以訪問window對象
    }
  }, false);