document对象的四个方法

 　　 //1.方法一
        function Write() {
            document.write("第一个方法");
        }
        //2.方法二
        function byId() {
            var d = document.getElementById("a").value;//根据id找值
            document.getElementById("b").innerHTML = d;//id=a标签的值给id=b
        }
        //3.方法三
        function Name() {
            var a = document.getElementsByName("1"); //根据id找值
            var b = "";
            for (var i = 0; i < a.length; i++) {
                b = b + a[i].value + "<br/>";//循环给b赋值
            }
            document.getElementById("b").innerHTML = b;
        }
        //4.方法四
        function TagName() {
            var a = document.getElementsByTagName("input");
            var d = "";
            for (var i = 0; i < a.length; i++) {
                d = d + a[i].value + "<br/>";
            }
            document.getElementById("b").innerHTML = d;
        } 

原文：http://www.cnblogs.com/wanmaoze/p/3517645.html