纠结的DOM 兼容性太差

var btn1 = document.createElement("input");
    btn1.type = "radio";
    btn1.name = "choose";
    var btn2 = document.createElement("input");
    btn2.type = "radio";
    btn2.name = "choose";
    var btn3 = document.createElement("input");
    btn3.type = "radio";
    btn3.name = "choose";

    document.body.appendChild(btn1);
    document.body.appendChild(btn2);
    document.body.appendChild(btn3);

    var all = document.getElementsByTagName("*");// 取不到文本节点 也取不到注释节点
    

    var images = document.images;
    console.log(images);
    /*var img = images.namedItem("mypic"); // chrome 不支持 IEff支持
    var img = images["mypic"];   // chrome 不支持 IEff支持
    alert(img);*/

    //alert(document.getElementById("user"));
    console.log(document.doctype);// IE 78 Null

    var xx = document.getElementById("xx");
    console.log("tagName", xx.tagName,"nodeName:", xx.nodeName);

    // .style 跟 getAttribute("style") 的差别
    console.log("style::", xx.style); // object
    console.log("getAttribute() style:::", xx.getAttribute("style"));
    
xx.removeAttribute("title");
    xx.onclick = function(){
        alert("寂寞的季节");
    };

    // .onclick 跟 getAttribute("onclick") 的差别
    console.log("1.onclick 作为 元素的属性：", xx.onclick);
    console.log("2. getAttribute('onclick')", xx.getAttribute("onclick"));
 
     //xx.setAttribute("mycolor", "red");
     xx.mycolor = "red";

    var yy = xx.cloneNode(true);
    document.body.appendChild(yy);




    var newNode = document.createElement("p");
    newNode.innerHTML = '<span> js 是怎样创建节点？ 怎样添加节点？ 不要跟jq 混淆</span>';
    var returnedNode = document.getElementById("xxx").appendChild(newNode);
    console.log(returnedNode == newNode);    // true
    console.log(returnedNode == document.getElementById("xxx").lastChild);// true

    document.body.appendChild(xx);// xx 已经是文档的一部分，结果是自己被挪动位置而已



    console.log(document.body.firstChild.nodeName);// firstChild 也存在兼容性问题 主要是ie7/8

    // slice array ie test
    var nodes = document.body.childNodes;
    //var arr = Array.prototype.slice.call(nodes, 0);
    //console.log("转化为数组", arr);

    function convertToArray(nodes){
        var arr = [];
        try{
            arr = Array.prototype.slice.call(nodes, 0);
        }catch(e){
            for(var i = 0,len = nodes.length; i < len; i++){
                arr.push(nodes[i]);
            }
        }
        return arr;
    }
    var array1 = convertToArray(nodes);
    console.log(array1[0]);
    console.log(array1);
    console.log(array1.length);
    //console.log(array1[4]);
    console.log(array1[2]);



    


    function Person(){

    }

    function assignEvents(){
        var id = "xx";

        
        document.getElementById("xx").onclick = function(e){
            for(var i = 0; i < 1000; i++){
                console.log(this);
            }
        };    

        id = null;
    }

    //assignEvents();
    //window.onload = function(){
        document.write("is right here in front of me "); // document.write() 在window.onload 之后会重写整个页面 跟jq 的domReady 一样
    //};