般来说，我们判断 iframe 是否加载完成其实与  采用的方法很类似：

var iframe = document.createElement("iframe");iframe.src = "http://www.planabc.net";if (!/*@cc_on!@*/0) { //if not IE        iframe.onload = function(){                alert("Local iframe is now loaded.");        };} else {        iframe.onreadystatechange = function(){//ie        if (iframe.readyState == "complete"){                        alert("Local iframe is now loaded.");        }    };}document.body.appendChild(iframe);

　最近，  文章的评论中 Christopher 提供了一个新的判断方法（很完美)

var iframe = document.createElement("iframe");iframe.src = "http://www.planabc.net";if (iframe.attachEvent){        iframe.attachEvent("onload", function(){                alert("Local iframe is now loaded.");        });} else {        iframe.onload = function(){                alert("Local iframe is now loaded.");        };}document.body.appendChild(iframe);