<div  id="login_form">

        <iframe id="login" onload = "onLoad" src="www.bbb.com/index.html" width="400px" height="650px" frameborder="no" scrolling="no"></iframe>

        </div>

 function onLoad() {

     var iframe = document.getElementById('login');

     var win = iframe.contentWindow;

     win.postMessage('{name:"ling",sex:"0"}','*')

 }

window.onmessage = function (e) {

    e = e || event;

    if (e.origin !== 'https://captcha.luosimao.com  bbb项目里用到的url但是项目aaa没有用到') {

        console.log(e.data)

    }

}