控制div属性

//首先创建公式，然后将需要改变的样式定义为数组，利用for循环查找位置，达到点击按钮改变相对应的样式。<script>    var changeStyle = function(elem, attr, value) {        elem.style[attr] = value    };    window.onload = function() {        var obtn = document.getElementsByTagName("input");        var oDiv = document.getElementById("box");        var oAtt = ["width", "height", "background", "display", "display"];        var oVal = ["200px", "200px", "red", "none", "block"];        for (var i = 0; i < obtn.length; i++) {            obtn[i].index = i;            obtn[i].onclick = function() {                this.index == obtn.length - 1 && (oDiv.style.cssText = "");                changeStyle(oDiv, oAtt[this.index], oVal[this.index])            }        }    };    </script>