javascript - JS获取元素对属性赋值失败

Question

在演示地址中,我对id为describe的子元素图片的尺寸进行统一赋值width="655",昨日都是正确的,今天调试过程中却失败,我的js代码地址为

window.onload = function(){
                    var prev = document.getElementById('prev');
                    var next = document.getElementById('next');
                    var sImg = document.getElementById('slider-img1');
                    var sCation = document.getElementById('slider-cation');
                    var arrayImg = ['http://dag1688.aliapp.com/wp-content/uploads/2015/11/dag-1.jpg','http://dag1688.aliapp.com/wp-content/uploads/2015/11/dag-2.jpg','http://dag1688.aliapp.com/wp-content/uploads/2015/11/dag-3.jpg','http://dag1688.aliapp.com/wp-content/uploads/2015/11/dag-4.jpg'];
                    var arrayText = ['大光五金旗舰店实拍','国际国内一线品牌代理商','30年五金机电行业服务经验','贵州省各大工矿企业优秀供应商'];
                    var num = 0;
                    
                    document.getElementById('pIcon').onmouseover = function () {
                        document.getElementById('pIcon').style.color = "green";
};
                    document.getElementById('pIcon').onmouseout = function () {
                        document.getElementById('pIcon').style.color = "gray";
};
                    document.getElementById('nIcon').onmouseover = function () {
                        document.getElementById('nIcon').style.color = "green";
};
                    document.getElementById('nIcon').onmouseout = function () {
                        document.getElementById('nIcon').style.color = "gray";
};
                    sImg.onmouseover = function(){
                        sImg.style.filter = "brightness(100%)";
                    };
                    
                    sImg.onmouseout = function(){
                        sImg.style.filter = "brightness(200%)";
                    };
                    //幻灯片初始化 

                function checkout (){
                            sImg.src = arrayImg[num];
                            sCation.innerHTML = arrayText[num];
                };
                    checkout();

                    prev.onclick = function(){
                          num --;
                            if(num==-1){
                                num = 3;
                            }
                            checkout();
                    };
                    next.onclick = function(){
                          num ++;
                            if(num == 4){
                                num = 0;
                                    }
                        checkout();
                    };
                    
// 以下是宽度为655的图片样本格式化
var pImg = document.getElementsByClassName('describe')[0];
var img = pImg.getElementsByTagName('img');
var htmlinline = document.getElementsByClassName('htmlinline')[0].innerHTML;
for(var nu =2;nu<img.length-5;nu++){
img[nu].alt = htmlinline;
img[nu].width = "655";
}
};

最后7行为演示错误的代码,请各位大神指教

Answer 1

你的测试地址中，

var pImg = document.getElementsByClassName('describe')[0];

获取到的DOM对象是：

<p class="describe">
      东西不错，比超市的要便宜。
</p>

木有图片啊...